Add cocoa powder and half of the almond milk to saucepan over medium heat and whisk vigorously to combine. Add remaining almond milk and bring mixture to a simmer, stirring occasionally, then remove from heat after 2-3 minutes.
To a large mixing bowl, add the egg yolks and whisk until they lighten in color. Gradually add the sugar in small increments while whisking vigorously so the two emulsify. You'll know you're done when it's thick and you achieve a ribboning effect - the mixture will form a ribbon when held from the whisk over the bowl.
Next, scoop in roughly 1/3 cup of the warm chocolate-almond milk mixture and whisk to combine, in order to temper the eggs. Add remaining liquid slowly and mix until completely combined.
Add xanthan gum to the mixture through a sifter and mix once more. This is not necessary, but will help the ice cream thicken.
Lastly, add the vanilla extract and stir once more. Then cover and refrigerate overnight or for at least 6-8 hours until completely cooled. Don't forget to chill your ice cream maker canister overnight as well.
Once chilled, pour the mixture into the pre-chilled ice cream container and prepare according to manufacturer's instructions. It should take 20-30 minutes.
Either consume immediately as "soft serve" consistency, or freeze, covered for 6-8 hours in a freezer-safe container to harden. Let set out for 10-15 minutes before scooping.