Heat oven to 350°F. Spray 24 regular-size muffin cups with cooking spray. In medium bowl, mix brownie mix, oil, water and eggs. Divide batter among muffin cups. Bake 13 to 18 minutes or until centers are set and toothpick inserted near edge of cupcake comes out clean. Cool 30 minutes. Run metal spatula around edge of each brownie; lift out to remove from muffin cup.