*For Personal Pan Size: Line a 4 x 8-inch or 5 x 9-inch loaf pan with foil. Spray with nonstick cooking spray and set aside. Preheat oven to 350 degrees. In a medium bowl, whisk together the brownie mix, melted butter (or oil), egg, vanilla, and water (or coffee). Add up to 1/4 cup "mix-in" ingredients, if desired, and stir. Spread into the bottom of prepared pan. Bake in preheated oven for 12-15 minutes, or until a toothpick comes out, 1-inch from edge with only a few crumbs. Cool before slicing.
**For 10-inch Skillet Brownies from Homemade Brownie Mix: Spray a 10-inch cast iron skillet with nonstick cooking spray, set aside. Preheat oven to 350 degrees. In a large bowl, whisk the brownie mix, melted butter (or oil), egg, vanilla, and water (or coffee). Add up to 1/2 cup "mix-in" ingredients, if desired, and stir. Spread into the bottom of prepared pan. Bake in preheated oven for 20-24 minutes, or until a toothpick comes out, 1-inch from edge with only a few crumbs. Cool before slicing.
***For Thin 9 x 13 Brownies from Homemade Brownie Mix: Spray a 9 x 13-inch baking pan with nonstick cooking spray, set aside. Preheat oven to 350 degrees. In a large bowl, whisk the brownie mix, melted butter (or oil), egg, vanilla, and water (or coffee). Add up to 1 cup "mix-in" ingredients, if desired, and stir. In a large bowl, whisk the brownie mix, melted butter (or oil), egg, vanilla, and water (or coffee). Add up to 1 cup "mix-in" ingredients, if desired, and stir.
****Thick 9 x 13 Brownies from Homemade Brownie Mix: Spray a 9 x 13-inch pan with nonstick cooking spray, set aside. Preheat oven to 350 degrees. In a large bowl, whisk the brownie mix, melted butter (or oil), egg, vanilla, and water (or coffee). Add up to 1 cup "mix-in" ingredients, if desired, and stir. Spread in bottom of prepared pan. Bake in preheated oven for 18-22 minutes, or until a toothpick comes out, 1-inch from edge, with only a few crumbs. Cool before slicing.