Preheat oven to 350º
Combine flour and baking powder, set aside
In mixer, cream butter and sugar well
Add half of the milk to creamed mixture until incorporated, add half of flour mixture likewise, repeat with other half of milk and then flour.
In 9 X 13 cake pan, spread batter evenly
Top that with canned peaches, either drained or with juice, depending on your preference.
combine sugar and cinnamon in separate bowl and sprinkle evenly over the peaches
Bake 1 hour or until cake is fully baked.