Mix Dry and Wet Ingredients:

For the donuts: Combine flour, sugar, cocoa powder, baking powder, baking soda, and salt in a bowl. Add eggs, milk, vanilla, and melted butter, mixing until smooth.

Pipe Batter into Pan:

Grease a donut pan with cooking spray. Transfer batter to a zip-top bag, snip a corner, and pipe into cups until about ¾ full. This yields 8-10 donuts.

Bake Donuts:

Bake at 325°F (165°C) for 11-14 minutes. Let cool slightly before removing from the pan.

Warm Glaze Ingredients:

For the glaze: In a small saucepan over medium-low heat, warm cream, milk, butter, vanilla, and corn syrup. Once the butter melts, add food coloring and remove from heat.

Whisk in Powdered Sugar:

Gradually whisk in powdered sugar until the glaze reaches the desired thickness.

Dip and Decorate Donuts:

Dip each donut into the glaze, then decorate with green dusting sugar and a single large red heart sprinkle.

Let Glaze Set:

Allow the glaze to set for several minutes before serving.