In the bowl of an electric mixer fitted with the dough hook attachment, combine flour, cocoa powder, and yeast.
Combine butter, sugar, salt, and boiling water in a small bowl.
Stir until butter melts.
Add evaporated milk.
Mix well.
Allow mixture to cool to room temperature.
Whisk in egg and egg yolk.
Pour over dry ingredients.
Mix at low speed for 1-2 minutes.
Increase speed to medium high.
Knead until dough becomes smooth, about 6-8 minutes.
Turn dough out onto a lightly floured surface.
Roll out to 3/16 inch.
Use a pizza cutter or sharp knife to cut beignets into 40 pieces.
Heat 2 inches of oil in a wide stockpot to 325℉.
Cook beignets, a few at a time, for about 1 minute per side.
When cooked through, remove from oil with a slotted spoon.
Drain on paper towels.