- Oven to 350°.
- Line an 8" square baking pan with foil, letting ends extend above pan on 2 sides.
- In a large bowl, mix oats, flour, brown sugar, baking soda and salt.
- Add melted butter and stir with a fork until evenly moistened (mixture will be crumbly). Reserve 1/2 cup crumb mixture for topping.
- Press remaining mixture evenly and firmly over bottom of ungreased, foil-lined pan. Bake 12 minute to set crust.
- Filling: In a small saucepan stir berries, sugar, cornstarch and lemon juice over med. heat until simmering.
- Simmer, stirring occasionally, until juices are no longer cloudy, about 2 minute.
- Spoon over crust. Crumble reserved crumb mixture over top.
- Bake for 30 minute.
- Let cool completely in pan.
- Lift foil by ends onto a cutting board.
- Peel off foil; cut into 2" squares.