In a large bowl, combine flour, baking powder, sugar, and salt. Stir until evenly mixed.
Add the cold cubed butter to the flour mixture. Use a pastry cutter, fork, or your hands to cut the butter into the flour until the mixture resembles coarse crumbs.
Store the mix in an airtight container at room temperature for up to 3 months. For longer storage, keep it in the fridge for up to 6 months.