Preheat the oven to 375 degrees F (190 degrees C). Generously spray or brush a nonstick donut pan with cooking spray; set aside until needed.
Place eggs, vegetable oil, and maple syrup into a mixing bowl and whisk thoroughly until the mixture is emulsified, light, and a little bit foamy, 3 to 4 minutes. Add almond flour, baking powder, salt, and cocoa powder; mix everything together thoroughly with a spatula until all the almond flour is incorporated and you've achieved a very thick batter.
Transfer batter into a pastry bag, or a plastic zip-top bag with one of the corners cut off. Pipe the batter evenly into the prepared donut pan.
Dip a finger in water and smooth the tops of the batter to even out. Tap the pan on a work surface a few times to settle the batter even more.
Bake in the center of the preheated oven until a wooden skewer inserted into a donut comes out clean, 9 to 10 minutes. Let cool in the pan for 10 minutes before inverting onto a wire cooling rack. Cool completely before serving.