Empty the box of brownie mix into a mixing bowl.
Stir in the oil and water. Whisk the mixture for a minute until it is thick and creamy.
Substitute an equal amount of leavening ingredient for two large eggs. For instance, 1 cup of applesauce equals two eggs; 1/4 cup of lemon juice mixed with 1 tablespoon of baking powder also creates a leavening action that mimics eggs.
Stir in your chosen leavening ingredient and whisk the brownie mixture for an additional minute.
Pour the finished brownie batter into the nonstick pan. Bake at 350 degrees for up to 35 minutes. Bake for 25 minutes if you like your brownies to be gooey and dense.