In a large bowl, place the gluten free oats, gluten free flour blend, vegan butter spread, and brown sugar. Use a pastry blender to mix it together. The mixture should resemble large crumbs, and there should be some balls of brown sugar and butter.
Place half of the crumble mixture in the bottom of a 8x8 square baking dish. Use your hands to pat it down.
Bake the bottom crust for 15 minutes. Remove from oven.
Put the blueberries in the pan, and spread evenly over the crust. Top with the remaining crumble mixture.
Bake at 375 degrees F for 25 minutes, until the berries are bubbling and the topping is golden brown.
Let cool before slicing into bars.
Notes
You can store leftover bars at room temperature for 3 days. If you want to keep them longer than that, store in the refrigerator.You can make these with different berries if you like. Try raspberries, strawberries, or blackberries.