Pre-heat oven to 350 degrees and spray a donut pan with non-stick cooking spray.
Mix all dry donut ingredients, then add wet donut ingredients and mix until well combined. Pour evenly into 6 donut cavities.
Bake at 350 degrees for 18-20 minutes or until a toothpick inserted into donuts comes out clean. Remove from donut pan to cool.
While donuts are cooling, heat white chocolate chips and coconut oil for 30 seconds at a time in the microwave until melted. Stir until smooth, then slowly add whey protein and whisk until smooth. Add peppermint extract and whisk until smooth. Pour into shallow bowl.
Dip donut tops into melted chocolate (or spread it on with a frosting spatula) and sprinkle with crushed candy canes.