Preheat the oven to 350 degrees. Use convection bake if you have it.
In a medium mixing bowl, partially melt the butter in the microwave.
Add the rest of the dry ingredients to the melted butter (oats, flour, brown sugar, salt and cinnamon). Stir well with a spoon or silicone spatula until the ingredients are fully incorporated.
Line an 8x8 baking pan with parchment paper (or grease it well). Press half of the oat mixture evenly throughout the bottom of the pan to form the crust.
Set the crust and the other half of the oat mixture aside.