Oatmeal Chocolate Chip Muffins

1 1/4 cups quick-cooking rolled oats
1 1/4 cups milk
1 egg
1/2 cup vegetable oil
3/4 cup firmly packed brown sugar, divided
3/4 cup semisweet chocolate chips
1 cup chopped pecans, divided
1 1/4 cup all-purpose flour
4 teaspoons baking powder
1 teaspoon salt

Combine oats and milk; allow to stand for 15 minutes. Preheat the oven to 400 degrees. Stir egg, oil, 1/2 cup brown sugar, chocolate chips, and 1/2 cup pecans into oat mixture. In large bowl, combine flour, baking powder, and salt. Add oat mixture to flour mixture, stirring just until all dry ingredients are moistened. Fill each cup of a lightly greased 12-cup muffin tin two-thirds full with batter. Sprinkle tops with remaining brown sugar and pecans. Bake 20 to 25 minutes, or until top of muffin springs back when lightly touched.