Sprinkle the reserved crumbs over the fruit filling. The crumbs won't completely cover the fruit.
Bake the bars for 35-45 minutes, or until the topping smells is light golden brown.
Cool the bars in the pan until they reach room temperature.
To make the glaze, whisk powdered sugar, vanilla, and milk together until combined.
½ cup powdered sugar, ½ teaspoon pure vanilla extract, 1 tablespoon milk
Drizzle over cooled bars, and cut into squares to serve.
Video
Notes
Oats: I haven't tried using quick oats in this recipe.
Flour: Feel free to substitute an equal amount of all-purpose flour for the white whole-wheat flour.
Strawberries: Frozen strawberries can be substituted for the fresh strawberries, but you may find that you need to make a couple of adjustments. First, you may need to add a few extra minutes to the baking time. Second, the filling may be thinner, so you might find that you need to add additional cornstarch to the filling to help it thicken properly.