Combine oats and milk and allow to stand for 15 minutes. Preheat oven to 200 degrees C. Grease each cup of one 12-cup muffin tin.
Stir egg, oil, 1/2 cup of the brown sugar, chocolate chips and 1/2 cup of the pecans into the oat and milk mixture.
Combine flour, baking powder and salt. Add oat mixture to flour mixture, stirring until just moist. Fill each cup of one 12-cup muffin tin 2/3 full. Sprinkle tops with the remaining brown sugar and pecans.