1/2cupmix-ins of choice: toasted walnutschocolate chips, crushed cookies (optional)
Place 1 1/2 cups of the oat milk in a large bowl and set a mesh strainer on top.
In a separate medium bowl, whisk together the egg yolks. Set near the stove.
Warm the remaining 1 1/2 cups of the oat milk, almond butter, sugar, salt, and cinnamon (if using) in a medium saucepan over medium-low heat, stirring until the almond butter melts and the mixture is smooth. Continue cooking, stirring often, until the mixture comes to a slight simmer, bubbling around the edges of the pan. Do not let come to a full boil.
Slowly pour the warm oat milk mixture into the egg yolks, adding in a little at a time, whisking constantly (do not add it too quickly or the eggs will scramble). Scrape the mixture back into the saucepan.
Stir the mixture constantly over medium heat with a heatproof spatula, scraping the bottom as you stir, until the mixture thickens slightly and easily coats the back of a spoon. DO NOT let the mixture boil. This will take about 3 minutes.
Pour the thickened mixture through the strainer into the bowl with the oat milk. Stir in the maple syrup and vanilla.
Let the mixture come to room temperature, then chill for at least 2 hours or overnight.
Freeze in your ice cream maker according to the manufacturer’s instructions (to make this oat milk ice cream without an ice cream maker, see notes). During the last few minutes of churning, add any mix-ins of choice. Enjoy!
*For a more neutral, classic vanilla flavor, swap the almond butter for cashew butter.
Because alcohol doesn't freeze, adding 1 tablespoon helps keep the oat milk ice cream softer, less icy, and more scoopable. For a completely neutral flavor, use vodka (you can't taste it!). If you enjoy whiskey, bourbon is a delicious addition to this ice cream. You also can omit the alcohol and let your ice cream sit out a bit longer before scooping.
TO STORE. Freeze for 3 months or longer.
TO SERVE. Homemade ice cream freezes harder than many store-bought brands. For easy scooping, let the oat milk ice cream sit at room temperature for several minutes prior to serving.
TO FREEZE WITHOUT AN ICE CREAM MACHINE: Prepare and chill the custard as directed. Pour into a deep stainless steel baking pan and freeze for 45 minutes. Once it begins to freeze near the edges, remove the pan from the freezer and with a spatula, stir the mixture thoroughly with a spatula. Return to the freezer. Check and energetically stir the mixture every 30 minutes. (A hand held mixer or blender works even better). Repeat every 30 minutes for 2 to 3 hours, or until the ice cream is frozen.