01 -
Preheat oven to 350°F and lightly grease a donut pan to prevent sticking.
02 -
In a medium bowl, whisk together flour, cornstarch, baking powder, baking soda, ground nutmeg, and granulated sugar until evenly mixed.
03 -
Add milk, sour cream, egg, melted butter, and vanilla extract to the dry mixture; stir gently until batter is smooth and free of lumps.
04 -
Transfer batter into a piping bag or resealable plastic bag with the corner cut off, then pipe batter evenly into donut cavities, filling each about two-thirds full.
05 -
Bake for 9 to 10 minutes until tops spring back lightly to touch and a toothpick inserted comes out clean; transfer to a wire rack to cool completely.
06 -
Melt chocolate wafers in short bursts in the microwave, stirring between; dip the bottom of each cooled donut into melted chocolate, placing chocolate side up on a rack to set.
07 -
Melt caramel candies with milk in the microwave, stirring until smooth; stir in salt and toasted coconut until well combined.
08 -
Spread the warm caramel coconut mixture evenly over each chocolate-coated donut; allow to set briefly, then drizzle remaining melted chocolate in a zigzag pattern over the tops.
09 -
Let the toppings fully set before serving or storing in an airtight container at room temperature.