Filling
1/2 cup brown sugar, firmly packed
2 tablespoons flour
1 tablespoon grated orange rind
2 tablespoons butter or margarine
2 cups crushed pineapple

Combine sugar and flour in saucepan; mix well. Add orange rind and butter. Gradually stir in pineapple; cook, stirring constantly until mixture thickens; cool and set aside.

Crumb Crust
1 cup brown sugar, firmly packed
1 cup quick oats
1 cup all-purpose flour
1/2 teaspoon baking soda
1/2 teaspoon salt
1/2 cup (1 stick) butter or margarine

Combine sugar, oats, flour, soda and salt; mix well. Stir in softened butter or margarine; set aside 1 cup crumb mixture. Pat remaining mixture evenly in greased 11 x 7-inch pan; spread cold filling over crust. Top with reserved crumb mixture. Bake in 350 degree F oven for 40 minutes. Cool.

Cut into 12 squares. Serve plain or with sweetened whipped cream.