Created by maDonna on October 18, 2015
Step 1: In a large bowl, cream the butter and brown sugar until light and fluffy. Combine the flour, oats, baking powder, baking soda and salt; gradually add to creamed mixture (mixture will be crumbly).
Step 2: Set aside 2 cups; pat remaining crumbs into a greased 13-in. x 9-in. baking pan. Bake at 350° for 15 minutes. Cool.
Step 3: Meanwhile, in a small saucepan, combine filling ingredients. Bring to a boil; cook and stir for 5-8 minutes. Pour over crust; sprinkle with reserved crumbs. Bake 15 minutes longer.