Preheat oven to 325 degrees F. Spray 2 donut pans with cooking spray; set aside.
In the bowl of a stand mixer fitted with the whisk attachment, combine yellow cake mix, eggs, pineapple juice, coconut milk and vegetable oil until batter is thick and smooth, about 2 minutes on medium speed.
Spoon or pipe batter into prepared pan, filling only about 1/2 way up the sides. Use an offset spatula or spoon to spread evenly, then bake for 12 minutes until donut cakes are set. Let cool 5 minutes on a wire rack, then invert cakes on rack to cool completely.
Melt the yellow and light cocoa candy melts according to instructions. Dip each donut into the melted yellow chocolate, dipping them deep enough to just fill the center. Remove and place on a wire rack set over a baking sheet. Let set completely.
Transfer melted light cocoa candy melts to a small squeeze bottle or pastry bag fitted with a small tip. Pipe crossing lines onto each donut, about 4 going in each direction. Top with pineapple top cutouts.