01 - Preheat oven to 350°F (175°C). Line a standard 12-cup muffin tin with paper liners or grease thoroughly with nonstick spray.
02 - In a large bowl, whisk together rolled oats, baking powder, ground cinnamon, and salt until evenly distributed.
03 - In a separate bowl, whisk applesauce, milk, eggs, honey or maple syrup, melted coconut oil or butter, and vanilla extract until smooth and fully blended.
04 - Pour the wet mixture into the dry ingredients. Stir thoroughly until all oats are moistened and the batter is uniform.
05 - Gently fold in blueberries, diced apples, chopped nuts, chocolate chips, or dried fruit if desired, taking care not to overmix.
06 - Divide the oatmeal mixture evenly among the 12 prepared muffin cups, filling each approximately 3/4 full.
07 - Bake for 22-25 minutes, or until the cups are set and lightly golden on top. Remove from oven and let cool in the pan for 10 minutes before transferring to a wire rack to cool completely.
08 - While oatmeal cups cool, stir plain Greek yogurt with 2 tablespoons honey or maple syrup until smooth and evenly sweetened.
09 - Once completely cooled, top each oatmeal cup with a spoonful of sweetened Greek yogurt. Garnish with fresh berries or sliced fruit before serving.