Preheat oven to 350°F. Grease a 12-cup muffin tin or line with paper liners.
Whisk eggs in a large bowl. Add pumpkin, milk, maple syrup, coconut oil, and vanilla; whisk until smooth.
In another bowl, combine oats, baking powder, pumpkin pie spice, cinnamon, and salt.
Stir dry ingredients into the pumpkin mixture until all oats are coated. Let sit 5 minutes to hydrate.
Fold in pecans and chocolate chips.
Spoon the mixture evenly into the muffin cups, packing it down slightly and filling nearly to the top.
Bake 24–28 minutes, until set and lightly browned on the edges.
Cool 10 minutes in the pan, then loosen edges and transfer to a rack to finish cooling.