Preheat oven to 350°F/175°C. Spray a donut pan with vegetable spray.
In a small bowl, prepare the flax egg and set it aside.
In a microwave-safe mixing bowl, add the vegan butter. Heat in a microwave until melted, around 20 seconds. Set aside.
Add the sugar, milk, vinegar, and flax egg. Stir to combine. Add food coloring drops if using. (See notes for food coloring options).
In another bowl, stir together the flour, baking powder, baking soda, and nutmeg.
Roughly chop the raspberries. You want raspberry pieces to present throughout the donuts. Stir it into the flour mixture.
Stir the liquid mixture and the flour mixture together until combined.
Use a spoon to evenly distribute the batter in each donut compartment, filling each to the top. This batter should fill up 6 compartments.
Bake 10 to 15 minutes, until the donuts are done and slightly golden colored on the top.
Remove from the oven and allow to cool for a couple of minutes.
Make the Raspberry Glaze by combining the powdered sugar and coconut oil in a bowl. Stir to combine. It will be a dry mixture. Mash the raspberries and stir them into the mixture. Then add the milk, one teaspoon at a time until you reach the desired, spreadable consistency.
Dip each donut in the glaze and then immediately coat it with coconut flakes, sprinkles, or your favorite toppings. Serve warm.