These are the easiest bars in the world. Take your favorite oatmeal streusel recipe and make it in a food processor. Take out half while the streusel is still sandy and reserve. Pulse the rest until it forms a soft, pliable dough that can be pressed into the bottom of a buttered 9-by-13 baking dish. Once the bottom layer is in the pan slice up a quart of fresh strawberries (preferably organic). Toss them with a tablespoon of cornstarch, 1/2 tablespoon of tapioca starch, and the juice of a lemon, and then scatter them over the bottom crust. Sprinkle the sandy streusel over the top and bake at 350°F for about 30 minutes, until the top streusel is golden brown and everything is cooked through. Let them cool to room temperature, slice, and serve. Improvisation at it's best.