Homemade key lime pie ice cream is a delicious summer snack. This recipe is a key lime curd in a coconut milk base, with crumbs of graham cracker crust mixed in. It makes about two pints. However, for the dairy-loving persuasion, I am sure it could be modified to work with regular cream.
This whole recipe is technically dairy-free, gluten free, and for all-intents and purposes, it's paleo-ish (the gluten free graham crackers have some sugar in them). Albeit, I doubt cave people made such delicious ice cream. In fact, I doubt they made ice cream at all. That part is irrelevant really. All I know is that it meets the dietary needs of my fiancé and is gosh-darn delicious.
Feel free to substitute in all the dairy and sugar you want, but I don't think it would really do much to improve it. In fact, I think the curd turns out better when using ghee instead of butter.
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Step 1: What You Need
For key lime curd ice cream:
2 Large Eggs (at room temperature)
3 Large Egg Yolks (at room temperature)
1/2 Cup maple syrup (at room temperature)
1/2 Cup lime juice (4-8 limes)
1 Tbsp lime zest (2 limes)
1 Pinch of Salt
6 tablespoons of ghee
1 can (13.5 oz.) full fat coconut milk
For the graham cracker crust:
2 Tbsp ghee
2 Tbsp maple syrup
1 Pinch of cinnamon (optional)
Required kitchen tools:
Ice Cream Maker (mine is a 1.5 Quart Cuisinart ICE-21)
Heat-proof mixing bowl
Fine mesh sieve
Reusable insulated ice cream tub and/or disposable ice cream pints
And assorted kitchen stuff
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Step 2: Juice the Limes
Juice the limes. The amount of juice you will get will depend on whether you use the larger more common Persian limes or the much smaller key limes. It should take about 4-6 Persian limes and about 6-8 key limes (in theory). Your mileage may vary.
Before you tear my head off about not using actual key limes, I would like to refer you to this side-by-side comparison or this other strong argument for using Persian limes in a key lime pie. Personally, I'd rather have taste over "authenticity."
Step 3: Zest the Limes
Zest two whole limes to create about 1 tablespoon of lime zest.
Step 4: Mix Most of the Ingredients Together
In a heat proof bowl whisk together the eggs, egg yolks, lime juice, maple syrup, salt, and lime zest.
Step 5: Simmer the Water
Fill a sauce pan with a few inches of water and bring it to a simmer.
Step 6: Add Ghee (or Butter)
Whisk in ghee one tablespoon at a time. Don't be shy in your measurements.
After about 3 or 4 tablespoons, I typically place the bowl atop of the sauce pan to encourage it all to combine better.
Continue adding ghee and whisking constantly until all 6 tablespoons have been added.
Step 7: Thicken the Lime Curd
Place the bowl over the sauce pan if you have not done so already.
Insert a candy thermometer.
Whisk constantly for about 7-10 minutes until the lime curd rises to 170 degrees and thickens.
I found the clip on the candy thermometer to not exactly be useful because the whisking often knocks it out of position. If you have this problem with your bowl, you can rig something up that works for yourself by attaching some binder clips to the candy thermometer's clip.
Step 8: Strain
Pour the lime curd through the fine mesh sieve. When complete there will be a leftover residue of zest and overly thickened curd.
It may be necessary to spoon some of this gunk out during the process if the strainer stops filtering.
Step 9: Mix in Coconut Milk
While it is still warm, mix in a can of full fat coconut milk.
Step 10: Cover and Refrigerate
Cover the bowl with saran wrap and refrigerate it until very cold. Typically, this is about 3 to 4 hours.
Step 11: Make a Graham Cracker Pie Crust
While the lemon curd ice cream is chilling, preheat an oven to 350 degrees.
Next, combine 1 cup of crushed graham crackers in a bowl with 2 tablespoons of butter, and 2 tablespoons of maple syrup.
Mix it all together until it forms a ball, and then flatten it out on a parchment paper-lined baking sheet as though you are making a 1/4" thick pie crust.
When done, stick it in the oven for 7-10 minutes until golden brown.
Once the crust has cooked, set it aside to cool for at least 30 minutes.
When the curst seems to have started to harden, crumble it up with your fingers into small pieces.
Step 13: Make the Ice Cream
Make the ice cream as specified by your ice cream maker.
When the ice cream is just about done, mix in the graham cracker crumbs so that they can get mixed throughout.
Step 14: Store Your Ice Cream
When its done churning, you can eat it right away if you want a soft-serve consistency.
However, if you want a harder ice cream, you will need to stick it in the freezer for a few hours.
Put your ice cream into whatever container you have available.
I like to fill one disposable pint with my creation for safe keeping, and put the rest in a reusable tub for immediate use.
The nice thing about storing some in a disposable pint is that it can also be gifted to people. No one is ever sad to receive homemade ice cream. Also, if you are over-zealous like me, you can make your own sticker logo and place it on the ice cream carton. This makes your ice cream seem real legit!