Key lime pie is one of my favorites. I love the tart/sweet combo. This summer, since we're still all social distancing and spending way more time in our own kitchens, I started experimenting with homemade ice creams. I have a Cuisinart ice cream maker (from Costco) and had been keeping the canister in the freezer thinking I'd like to make ice cream now that it was hot outside. Fourth of July weekend was a perfect excuse.
This custard-based ice cream is easy, but you need to plan ahead. You CAN make it the day you want to eat it, but if you can mix it up the night before you'll have more flexibility in having it ready when you want to eat it. You need to plan for about 30 minutes making the custard, 2-4 hours to cool it (I start with an ice bath and then the fridge to speed things along), 30 minutes to churn and then 3-4 hours to freeze before serving (ok, you can serve it right after churning as a very soft serve).
This recipe uses a little bit of corn syrup, which helps reduce ice crystal formation, so that you don't get grainy ice cream.
Ingredients
1 1/2 C. half and half
1 C. heavy cream
3/4 C. sugar
2 Tbs. corn syrup
1/8 tsp. salt
5 egg yolks
2 Tbs. lime zest (around 3-4 limes)
1/2 C. fresh lime juice
Crust cookie "add in"
5 whole graham crackers
3 Tbs. sugar
1/4 C. melted butter
Equipment needed
Medium saucepan
Medium bowl
Fine mesh strainer
Citrus zester
Ice cream maker
8x8 baking dish or a large loaf pan
Thermometer (opt)
Get things set up before you start so that you can work efficiently. Does your ice cream maker need the canister to be frozen in advance? Make sure you've got that taken care of!
1. Crack the egg yolks into a medium bowl and whisk, set aside.
2. Zest the limes, set aside.
3. Juice the limes, set aside.
4. Make the custard. In a saucepan add the half & half, cream sugar, lime zest, corn syrup and salt. Heat on medium stirring constantly until sugar is dissolved and you start to see bubbles around the edge-do NOT boil. Slowly pour a thin stream of the hot cream mixture into the egg yolks, whisking constantly. This will bring the eggs up to a higher temperature without scrambling them. Pour the hot mixture back into the saucepan and keep cooking on medium and stirring with a wooden spoon until the custard coats the back of the spoon (its about 175-180 degrees)--about 3-5 minutes of cooking. Do NOT let it boil. You'll notice it become thicker and bubble around the edges. While it cooks, wash out the bowl that held the eggs so it is ready for the finished custard.
5. Pour the hot custard through a fine mesh strainer back into the clean bowl--this will strain out the zest and any eggy bits. Also pour the lime juice into the custard through the strainer (catches any seeds or pulp). Stir it up. Resist licking the spoon. Cover with a piece of plastic wrap placed right on the surface of the custard to avoid a film forming.
6. You need to cool the custard down to 40 degrees. You can just refrigerate it overnight or you can speed things along by putting the bowl into a bowl of ice water.
7. Make the crust cookies. I like to add the cookie bits to the ice cream, although you could leave them out or just sprinkle them on a bowl when serving. In a gallon zipper bag add the graham crackers and crush with a rolling pin. Add the sugar and butter and mix right in the bag. Pour onto a parchment lined baking sheet, press into a giant cookie that is about 1/4 inch thick and bake for 5-7 minutes at 350 until golden. Let cool. Crumble. I added about 1 T of shredded coconut to my mix before baking because I love it, but I know lots of folks don't.
8. Churn the custard! You are getting closer. First, get the 8x8 baking dish and line it with plastic wrap. Get your ice cream machine going (mine requires that I freeze the canister at least 24 hours, so I just store it in the freezer). Follow the directions on your machine and add the cooled custard. It will take around 30 minutes to become a very thick soft-serve.
9. Scoop the custard into the prepared 8x8 dish, smooth it out, sprinkle it with the crust cookies and press them in. Cover with more plastic wrap and pop into the freezer for 3-4 hours. This will let it firm up enough to scoop and put on cones. You will definitely want to lick the dasher from the ice cream machine at this point.
This ice cream is so delicious. Serve it on your favorite cone or just dig in with a spoon.
Lemon variation
If you also like lemon meringue pie, you could do this with lemons instead. Increase the lemon juice to 2/3 C. Everything else is the same. I made this version too and left out the crust cookies--reminded me of Aggie Ice cream from USU. Only better. And closer to home.
