Preheat the oven to 350°F and spray a mini muffin tin with nonstick spray.
In a large bowl, whisk together the eggs, Greek yogurt, milk, maple syrup, and vanilla.
2 large eggs, 1/2 cup plain Greek yogurt, 3 Tablespoons milk, 2 Tablespoons maple syrup or stevia, 1 teaspoon vanilla extract
In a separate bowl, stir together the oat flour, protein powder, baking powder, salt, optional flax meal, and mini chocolate chips.
1 1/2 cups oat flour, 2 scoops vanilla protein powder, 1 1/2 teaspoons baking powder, 1/2 teaspoon salt, 1-2 Tablespoons flax meal, 1/4 cup mini chocolate chips
Add the dry ingredients to the wet ingredients and stir until combined. Let the batter rest on the counter for 15–20 minutes so the oat flour can absorb the liquid.
Stir the batter well again, especially if using chocolate chips. Use a heaping tablespoon to divide the batter between the prepared mini muffin cups, filling them all the way.
Bake for 11–12 minutes, until the tops are set and a toothpick inserted into the center comes out with a few moist crumbs. Cool slightly in the muffin tin and serve warm, or store for later.