Warm in a 350 degrees F oven about 5 minutes or until butter
is melted. (Be sure to watch carefully to avoid overbrowning the butter).
Remove pan from oven.
Mix the cinnamon well into the brown sugar.
Add brown sugar, stirring
until sugar is completely moistened. Spread sugar mixture evenly in pan.
Arrange peach slices evenly over brown sugar mixture. Set aside.
In a medium bowl, combine the flour, baking
powder and salt; set aside.
In a large bowl, beat 1/2 cup butter with an
electric mixer on medium to high speed for 30 seconds.
Beat in granulated sugar
until well combined.
Blend egg and vanilla for 1
minute in the blender
Alternately. add the flour
mixture and milk to beaten butter mixture, beating on low speed after each
addition just until combined.
Spread batter evenly over the peaches in the pan.
Bake for 45 to 50 minutes or until a wooden
toothpick inserted near the center comes out clean.