Ice cream made with sweet potatoes? Who would think up such a thing? As soon as we saw it in Mashed, by Holly Herrick, we knew that this was something we just had to try. After all, with this recipe you can eat your ice cream and call it vegetables!
Just kidding, of course; it’s still ice cream, even though you’ve added a tuber.
We will say that we changed this recipe, and perhaps in not significant ways — all for the better, we think; first we didn’t have the called-for pumpkin pie spice, so we used ginger, cloves, and nutmeg. For ice cream, we really prefer steeping whole cinnamon sticks in the heated half-and-half, and we can’t imagine making an ice cream without a blender and straining multiple times to ensure a smooth creamy dessert.
For the sweet potato, you can use leftovers, unless you’re like us and never have leftover sweet potatoes. In which case, you can quickly cook one by popping it into a microwave. We do it thusly: 5 minutes on high, 5 minutes resting, 5 minutes on high, 5 minutes resting, done. If you don’t have cinnamon sticks, substitute about a teaspoon of ground cinnamon.
Procedure in detail:
Heat and steep. In a medium saucepan, combine half-and-half, cinnamon stick, ginger, nutmeg, cloves, salt, and about half the sugar. There’s no need to get the amount of sugar exact; just measure out the 3/4 cup of sugar and pour about half of it into the half-and-half mixture, saving the remainder for later. Bring to a low simmer (around 170°F), stirring often. Turn off heat, cover, and let steep 30 minutes.
Strain and blend. Place the cooked sweet potato in a blender. Pick out the large pieces of spices from the half-and-half and discard. Strain half-and-half mixture into the blender. Blend on high until very smooth. In a high-powered blender, this may take about a minute, but the time will vary, so visually check the smoothness. While blending, quickly wash the saucepan.
Reheat. Strain the mixture back into the now-clean saucepan and place over medium heat. Bring the mixture back to a low simmer (about 170°F), stirring very often.
Whisk egg yolks and sugar. In a medium bowl, whisk together the egg yolks and remaining sugar until smooth and pale yellow.
Temper. Tempering the egg yolks is the hardest, and most crucial, part of making ice cream, but don’t worry, it’s not that bad. Start by whisking the egg yolk mixture briskly. While whisking, slowly start adding just a bit of the hot half-and-half mixture and wait for it to whisk in. Now add a bit more — all the while whisking — and a bit more. Each time you add the hot liquid, use just a bit more. Continue whisking and adding until most or all the hot liquid is incorporated. Return the mixture to the saucepan
Cook custard. Return the mixture to medium heat and cook, stirring continuously, until the mixture is at a bare simmer and thickens slightly. If you use a thermometer, you’ll want the temperature between 165-170°F. Hotter than that and the egg yolks will congeal, forming small lumps.
Strain. Pour the custard through a fine-mesh strainer into a medium-sized bowl. This straining should catch any small bits of congealed egg, bits of spices that are left, and make your ice cream smooth.
Add cream and vanilla. Stir in the heavy cream and vanilla and cover with plastic wrap.
Chill. Place the custard mix in the refrigerate and chill overnight. This will allow the spices to meld, and, by having the custard thoroughly cold, it’ll churn into ice cream faster.
Churn. Set up your ice cream machine and churn according to the manufacturers’ directions. Ours is an attachment for our KitchenAid mixer, and we love it.
Mix in macadamia nuts. Once churned, stir in those chopped macadamia nuts.
Pack. Pack all the ice cream (except what you eat, of course) into an airtight container and place in the freezer.
We had a little fun with this ice cream flavor. We brought small cups down to our Monday night walk and handed them out to volunteers with the challenge to figure out the flavor. The response closest to the correct flavor was butternut, but the rest ranged from mango (because of the color and before a taste) to eggnog. Any of which would also make a good flavor for ice cream. Five sweet stars.