There are many different ways to cook a whole pig. You might be familiar with the spit method, or the burying method. This instructable will cover the use of the Cajun Microwave for cooking your pig, including preparation, cooking, and some notes on hosting a pig roast.
What is a Cajun Microwave?
A Cajun Microwave is a wooden box with a metal tray on top. You put the pig into the box, and build a fire in the tray. Because the box holds heat well, and the cooking heat is radiant rather than direct, it's perfect for Low and Slow Southern BBQ. The exact origins of the Cajun Microwave are contested, however, a nearly identical product is available in Florida, by way of Cuba, called "La Caja China" or "The Chinese Box"
In Louisiana, it is traditional to build the box out of cypress boards and leave it unlined. Others build them with reflective metal liners, or insulation. The commercial "La Caja China" is built of plywood and lined with aluminum.
Whatever the origins of the Cajun Microwave, it is essentially a giant dutch oven, it does a great job at cooking large amounts of meat evenly and (relatively) quickly. For most of the instructable, I will just refer to the Cajun Microwave as the "Roaster".
One final disclaimer:
I am from Alaska. Everything I know about Cajun Microwaves I learned on the internet. I have been doing this for several years now, and feel like I have a pretty good grasp of the use of a Cajun Microwave to make tender pulled pork bbq. However, I make no claims to Cajun or Southern Authenticity.
On the other hand, I did eat gator once, and liked it just fine, so there you go.
Step 1: Required Items
Here is a list of things you will need:
Turkey Roasting Pan
Step 2: Order Your Pig
When picking a pig, make sure you communicate to your butcher that you want a whole pig for a pig roast. You will also need to tell them how big of a pig you want, and when you want to pick it up. Also if they know that the pig is going to be roasted whole, they should know to remove the hair.
Pigs come covered in fur, but when your pig arrives, it should be hairless. Think about that for a second. The next time you are sitting at work, feeling sorry for yourself, you could be shaving dead pigs for a living.
Pig Sizing Guide:
A rough rule of thumb is 2-3 pounds of pig per person. I recently did an 83# pig for 15 people, but we had to send people home with ziploc bags full of pulled pork. I believe we had five 1-gallon bags of leftovers.
Sure, you could buy a pig from another state, or another country, but you shouldn't. Buying locally reduces the distance your food has traveled, and thus the environmental impact. Also, if you buy locally, you can visit the farm to see if the conditions are to your liking. Many small farms are going to hormone free / organic farming, and you can often get a much healthier pig this way. However, you don't have to be some sort of leftwing nutjob to buy locally. Doing so results in higher quality, fresher food, and keeps your money in the community. I think we can all support that.
Step 3: Site Selection, Invitations and Deputies
Where will you hold the pig roast? If you have lots of room at your house, that's great. If not, you have to find a public picnic area which will allow you have have a fire. It should also have access to water, and restrooms of some sort. I like to visit the site ahead of time, just to make sure it will work.
Once you get the site reserved and a date picked, you have to send out invitations via Email, Facebook, Pidgeon, whatever you use.
Make sure to include instructions to get to the site, if it is remote, as well as specific instructions about what to bring. Part of the key to these things is making sure that people bring a bunch of great food and drink to share. Assigning items to bring might be a good way to avoid duplications.
As the person in charge of the pig, you are going to be busy. After spending all day feeding the fire, suddenly the pig is done and ready, and all your guests are here. You don't have time to find plates or search for ice. Get a few deputies, involve them in the planning of the event, and have them help out during. One or two should be good.
Step 4: Take Delivery of Pig & Thaw It Out
Unless you ask your butcher to thaw it out for you, the pig will arrive frozen solid. It's going to take a few days to thaw something this large. If you can get the butcher to thaw it for you, DO IT!
I typically obtain a large cardboard box and line it with a heavy plastic bag. Place your pig inside, and cover the pig with salt. I would start this process 2-3 days prior to the pig roast.
After a day or so, thin parts will start to thaw out, like the bacon, and the ribs. You will have to start putting ice on these parts to keep them cold while allowing the shoulders and hindquarters to thaw out.
The important point is to keep the pig just cold enough to prevent spoiling, but warm enough to allow it to thaw. Don't worry too much if the pig is still a little frozen on roasting day.
Step 5: Preparing the Pig
In order to speed the process of roasting, you need to butterfly the pig. Butterflying means that you cut the backbone from pelvis to skull, to allow the pig to lay flat. This is really not as hard as it sounds.
At an absolute minimum, you need a cheap, heavy chef's knife, and a standard hammer and a Bone Saw. A proper bone saw is preferred, but any hand saw would work.
Step 1 - Start at the tail end of the pig, with the pig on it's back. Using the saw, cut open the front of the pelvis and encourage (by force) the hind quarters to lay flat. You should see the back of the pelvis, and the start of the backbone.
Step 2 - Move to the head, and use the saw to cut open the breastbone; start the cut on the tail end, and cut up to the head. The rib cage should open slightly.
Step 3 - Go back to the tail, use the bone saw to start cutting the backbone near the pelvis, once you have a cut started, switch to the knife.
Place you knife horizontally along the backbone, and pound the back of the knife with the hammer a few times. The vertebrae are surprisingly soft, and the blade should cut right through. Repeat this process several times, each time cutting through 3-4 vertebrae. The pig should start to lay flat. Make sure that you don't cut beyond the vertebrae - it's easy to cut too far and come out the top of the pig. This will make an unsightly hole.
When you reach the back of the head, you have a choice to make. The pig will lie flatter and cook better if you cut the back of the skull in half with your saw. It's possible that this last step might be too much for some people. If so, skip it, but your pig won't cook quite as evenly.
Once the pig is butterflied, cover the interior with kosher or rock salt and your rub of choice, and place into the pig rack. I don't have a favorite rub recipe, so I just use Tony Chachere's rub, available at your supermarket. If you have a marinade injector, this is a good time to juice up the pig with your marinade of choice.
If you want to butterfly the pig the night before the roast, simply rack the pig, and fill the bottom of the roaster with ice. Unless you live somewhere really warm, that should keep it cool until the roast.
Step 6: Setting Up Roaster & the Pig
Prior to the pig roast, assemble your roaster and make sure all the parts are there. If this is an annual pig roast, you may have forgotten or lost parts along the way.
If you built a roaster, hopefully you will know how to operate it. If you bought one, follow the instructions that came with it.
In general, you want to set it up on a level surface, away from anything that could catch on fire. If the bottom tray has a drain, make sure the drain is downhill, otherwise, you will have a couple of gallons of pig grease to deal with later. Set up your firewood pile nearby, so that you don't have to stray too far to get it.
Locate your thermometers, and make sure they work, placing them inside the roaster as needed.
If you have not mounted the pig in the cooking rack, that's the last thing to do prior to starting the fire. Once inside the cooking rack, place the pig into the roaster, and install thermometer probes. Make sure that pig is bone side up for the first part of the cooking. This allows us to crisp the skin when we flip the pig.
If you didn't already do it, shake a couple of cups of kosher salt onto the pig, follow that up with your rub. If you don't have a favorite rub, just use Tony Chachere's Creole Seasoning.
Step 7: Cooking and Monitoring
With the pig inside the roaster, put the lid on and build a fire on top. I like to build two small fires on either end of the fire tray. Remember at this point that you have lots of time, and can build the fire slowly. Your goal is to keep the roaster temperature between 275 and 300. You can control the heat in the roaster by spreading you coals out and adding wood to make it hotter, or by forming piles at either end with the coals to make it cooler.
Use hardwood firewood to build a fire, not charcoal briquettes. It has been my experience that over the 8 or so hours the pig takes to cook, the briquettes build up too much ash, which slows the cooking.
Hopefully, you have a wired thermometer installed in the pig. It needs to be placed in the shoulder or in the leg - find the thickest part of the pig, and put the thermometer there. I have a nice one which displays air temperature and pig temperature. However you do it, you need to have a way to remotely monitor the temperature of both the roaster and the pig.
YOU CANNOT OPEN THE ROASTER TO CHECK ON THE PIG, THAT LETS THE HEAT OUT!
The roaster should only be opened twice, once to flip, and once to eat. No peeking, no exceptions.
Once the pig reaches about 150 degrees, it's time to move on to the next step, flipping!
Step 8: Flipping and It's Ready!
Flipping the pig is important for even cooking, and allows you to crisp the skin prior to removal. If the pig was skin side up the entire time, the top would be burned beyond recognition.
Once the pig reaches around 150 or so, I like to flip it. Have welding gloves and a friend handy. Remove the fire tray, flip the pig, and put it back. Do this step as quickly as possible to keep as much heat in as you can. Make sure that the thermometer probes are correctly placed before putting the fire try back on.
After flipping, the pig temperature may drop, and it may take an hour for the temps to start rising again. It's ok. It takes a while for the heat to get through the skin and fat on the top side of the pig.
When the pig reaches 195 degrees, get it out of there! It's done!
Step 9: Serving the Pig
Once the pig is done, put down a heavy plastic sheet or table cloth on a picnic table, and put the pig rack on that. Open the rack and remove the top half. I like to serve into a turkey roasting pan, that way I can juice the pulled pork with a sauce before it goes out.
A Note on BBQ Sauce:
This is a hotly debated topic. Pick a BBQ sauce you like, and serve that. I have been trying recipes online, and have yet to find one I love. Store bought is often too thick, and lacks enthusiasm. Just try to find one or two bottles you are happy with and make that available. My preference is to use a vinegar based sauce on the pig as it comes out of the roaster, and then allow people to use BBQ sauce to taste for themselves.
If you were successful, you should be able to get the pork off the bones using only a pair of tongs. It should be that tender. You may want to task a deputy with the job of serving the prepared pork, otherwise, just set out the roasting pan, and allow people to serve themselves.
Additionally, if you want pictures of the final pig, have somebody else do it. You will be busy. Trust me. My last pig roast, the pig looked epic, but no pictures, because I was busy, and I forgot to ask someone to do it for me.
Step 10: Final Pig Roast Suggestions
People show up at a pig roast looking for a good time. It isn't hard to provide that.
Make sure some beer and soda is available, and that you have a way to keep your guests warm and out of the rain. Somebody should be tasked with bringing some outdoor games, or possibly a portable stereo.
Depending upon the size of the pig, you should expect to spend 8 - 10 hours cooking. Don't follow a timer however, only remove the pig when it reaches temperature!
Expect to stay later than you expect. A gas lantern is helpful in this regard. It also helps if you keep a deputy or two around until the end to help clean up.
Finally, I typically hold my roast in fairly rural campsites. We have not had bear problems yet, but it could always happen. If you have animal problems in your area, prepare for an encounter and don't leave food out. Before you leave, make sure that your site is clean and free from piggy parts. Before you put the roaster away, make sure to get it as clean as possible.