01 -
Preheat the oven to 190°C. Grease or line a 12-cup muffin tin with paper liners.
02 -
In a large mixing bowl, whisk together the milk, eggs, maple syrup, applesauce, and vanilla extract until smooth.
03 -
Add the oats, baking powder, cinnamon, nutmeg, and salt to the wet mixture. Stir until fully combined.
04 -
Gently fold in the chopped apple and, if using, the chopped walnuts or pecans.
05 -
Spoon the mixture evenly into each prepared muffin cup, filling them nearly full.
06 -
Sprinkle coarse sugar on top of each cup if desired for added texture and sweetness.
07 -
Bake for 25 to 30 minutes until the tops are golden and a toothpick inserted into the center comes out clean.
08 -
Allow the cups to cool in the muffin tin for several minutes before transferring them to a wire rack to cool completely.