Step 1

Preheat oven to 350°F.

Step 2

Combine flour, sugars, and cinnamon in a bowl; cut in the butter with a pastry blender/cutter until butter is the size of small peas. This can also be done by pulsing in a food processor or using your fingers to press the butter into the flour until the mixture is crumbly. I like to use my fingers because the warmth of your fingers soften the butter just enough to bring the mixture together somewhere between a ball of dough and dry and crumbly. (I don’t add the oats until after this step because it cuts the oats into tiny bits.)

Step 3

Stir in oats. I used quick cooking oats in this photo because I had it on hand but I prefer the look and texture of old-fashioned oats.

Step 4

Combine all the ingredients for filling in a large bowl and stir gently to coat the fruit. Frozen fruit can also be used but be sure to pat dry with paper towels to remove water when they thaw. Spoon filling into a greased 9-inch square baking dish or 2-quart casserole. Spoon, sprinkle, or dollop the topping mixture onto the filling and bake at 350° for 45 minutes or until the topping is golden brown and the filling is bubbly.