Preheat oven to 400°F. In a large bowl, combine flour, baking powder, and salt. Make a well in the center.

In a large mixing bowl, beat softened butter, sugar, and egg until blended. Add milk and vanilla, and beat until combined.

Pour wet ingredients into the dry mixture. Add chopped pecans and stir until just moistened.

In a small bowl, mix brown sugar, flour, and cinnamon to make the spice topping.

Line a muffin pan with paper liners. Spoon about a teaspoon of batter into each cup, sprinkle with spice mix, then top with remaining batter and remaining spice mix.

Bake for 20 minutes, or until a toothpick inserted into the center comes out clean.