The main problem most people have with unglazed stoneware is that food can stick. This is especially a problem with new stoneware. After repeated use (especially with fatty foods), stoneware developes a dark, non-stick, breathable layer. This process is called "seasoning". A frequently used expression is "The worse it looks, the better it cooks". A seasoned stoneware pan is a joy to cook with, but it can take many uses to achieve that seasoning.
Fortunately you can speed this process up quite a lot by pre-seasoning your new stoneware. The process is virtually identical to the process used to season cast iron. We will use Flax seed oil. Flax oil is used because unlike most oils, it is a "drying oil". When heated past it's smoke point, the molecules bind together into a very hard glaze. This material is highly heat resistant, and should also be fairly resistant to soap, but you should still avoid cleaning with soap. Instead use a plastic scraper or brush. This process also happens very slowly when flax oil is exposed to air at room temperature as well, which is why it is used in oil paint and furniture finishes (although artists and carpenters call it linseed oil, and linseed oil often contains additives that make it inedible and not safe for seasoning pans)
Be aware that this process may make your kitchen smell a bit strangely. Raw flax oil has an unusual, slightly "grassy" smell, and the process may produce a little bit of smoke (especially if you don't wipe off excess oil). Remember, we will be intentionally heating the oil past it's smoke point, so you might want to run a fan or open a window to prevent setting off your smoke detector. You could probably do this in a back yard grill too, although controlling the temperature would be difficult.
You will need:
Unglazed stoneware pan
food grade flax seed oil
lint-free cotton cloth that you don't mind ruining (rags).
The process: (note, you will repeat these steps several times, to build up several very thin coats of seasoning.)
Step 1. Get an unglazed stoneware pan. Glazed stoneware does not need to be seasoned, and you might just ruin a perfectly good glazed pan if you try this process. When shopping for a pan, feel the inside of the pan. it should be a fine, sand-papery texture, but should not have any large bumps.
Step 2. Pre-heat an oven to 450.
Step 3. Using your fingers, wipe a thin layer of flax oil on the inside of the pan,
- Be sure it is clean and completely dry before starting.
- Wipe the oil anywhere food might be in contact with the pan.
- Don't forget areas that might get dripped on, like between muffin cups. let it soak in for a few minutes.
Step 4. Use the cotton fabric to wipe as much oil off as you can.
- It should look damp, but not shiny, and there should be no "brush marks", puddles, or drips. Excess oil will also increase the amount of smoke this creates.
- Be careful not to leave any lint or dust on the surface, because any lint that is left on the surface will become fused to the seasoning layer. This is especially a problem if you use paper towels to wipe the oil off. Paper towels leave lots of fine linty fibers that are almost invisible, but they will become clearly visible after baking. If that happens you may have to use a small piece of fine sandpaper to smooth the surface.
- Be careful when disposing of flax oil soaked rags. The same chemical reaction that causes flax oil to harden when exposed to air also produces heat, and oil soaked rags can catch fire. Soak the rags in water and put in an airtight container like a jar before throwing away
Step 5. Bake it for 30 minutes at 450. Don't open the pan to check, just turn off the oven after the time is finished, and let it cool down slowly. This helps contain some of the smoke, and gives the coating a little more time to harden.
Step 6. Remove, and notice the nice, evenly brown patina. It looks like your pan spent a weekend in the Bahamas. You may have a few darker or lighter areas. The more even the coating, the more even the color. it should not feel sticky or oily, because the oil has polymerized and formed a hard, thin layer.
Step 7. Repeat steps 2-6 at least 3 times. As layers build up the pan will gain a slick, hard semi-gloss caramel colored finish that would otherwise take many uses to create.
Step 8. Bake things!!
- For wet "batter" foods, like quick breads and cupcakes, first lightly coat the pan with a thin layer of butter or oil, then dust with flour and blow off the excess, before adding the batter. This trick also works for metal pans.
- For stiffer, dryer doughs, like bread or pizza dough, dust the bottom of the dough with flour and cornmeal. I use corn tortilla flour (masa), but any cornmeal works fine.