Wash hands with warm, soapy water for 20 seconds.
Preheat oven to 350°F and spray baking an 8x8-inch baking pan with nonstick spray.
If using fresh pears, wash them. If using canned pears, drain them, saving 1 Tablespoon of liquid.
Core pears (if fresh) and cut into bite-sized pieces or thin slices.
Arrange pears and blueberries in baking pan.
Mix water or liquid from canned fruit with cornstarch or 1 Tablespoon of flour and pour over fruit.
Mix together oats, sugar, flour, and margarine. Stir in nuts or seeds.
Sprinkle evenly over fruit. Bake at 350°F for 20 minutes.
Enjoy warm or cold.