Cream 3/4 cup butter, 1/2 cup sugar, and 1/2 cup brown sugar. Add eggs and 1 tsp. vanilla. Mix in flour, 1 tsp. cinnamon and baking powder. Blend in zucchini.
Pour into greased jelly roll pan and bake at 350 degrees for 25 - 30 minutes. While baking, prepare the frosting.
Frosting: Mix the 2 cups powdered sugar, cinnamon, melted butter, vanilla, and milk. Mix until creamy. Add additional milk, if necessary, to get desired consistency. Cool zucchini bars and frost. Cut into squares. ENJOY!!!