Preheat oven to 350 F. Line a 12 cup muffin pan with paper cups.
In a small bowl, combine all topping ingredients & set aside.
In a large bowl, combine flour, oatmeal, brown sugar, baking powder, baking soda, salt & spices. With a pastry blender, cut in butter until it resembles coarse crumbs.
In another bowl, whisk together egg, liqueur, milk & pumpkin puree. Stir into flour mixture JUST until moistened. Place a small scoop of batter in each cup. Divide topping. Using half of topping, divide evenly between cupcakes, creating the ‘filling’ for the cupcakes. Divide remaining batter between cups; top with remaining topping. Bake 15-20 minutes or until they test done. Remove from pan & cool on a wire rack.
Recipe Notes
Technically, pepitas and pumpkin seeds are the same thing. But pepitas (which mean “little seeds of squash” in Spanish) don’t have a shell and are found in only select pumpkin varieties.