Preheat the oven to 350 Fahrenheit.
Spray a 12-14 ounce ramekin with oil and set aside.
Whisk together all wet ingredients in a bowl until smooth, start with just 2 tablespoons of milk.
Mix in the dry ingredients. Feel free to add in any other mix-ins at this point such as berries, nuts etc.
If your batter seems too thick/dry, add in the remaining two tablespoons of milk. How much you need will depend on the exact protein powder you used.
Transfer to your ramekin and top with chocolate chips if desired.
Bake for 18-22 minutes or until a toothpick comes out clean. If you like a more well done center, just bake for longer!
Remove from the oven and let cool for 5-10 minutes, then serve! I love topping mine with fresh berries or sliced banana.