In a large bowl, combine flour, baking powder, cinnamon and salt. In another bowl, beat the eggs, milk, oil, sugar and vanilla until smooth. Stir into dry ingredients just until moistened. Into each greased muffin cup, spoon 1 tsp butter, 1 tsp brown sugar and 1 heaping tablespoon of pecans. Top each with 1/4 cup of batter. Bake at 350oF for 25 to 30 minutes or until muffins test done. Invert pan onto a piece of foil. Let stand for 2 minutes; remove from pan. Serve warm.
1/4 cup butter or margarine, melted
1/4 cup packed brown sugar
1 cup chopped pecans