Combine approx. 2 cups of berries. Pictured: blueberries, raspberries and sliced strawberries. Sprinkle fresh lemon juice and sugar over and sit while prepping the topping. Combine approx. 2 cups rolled oats, brown sugar to taste, small amount of flour and enough butter to adhere the mixture together. Pour berries into pan, sprinkle on topping and bake at 350 until desired done-ness. About 40 min. Serve immediately over vanilla ice cream ?