Combine hot water and 2 teaspoons coffee granules in a medium bowl; stir well. Add brownie mix, teaspoon vanilla, and egg whites; stir until well blended. Pour mixture into a 9-inch pieplate coated with cooking spray. Bake at 325 degrees for 22 minutes. Let crust cool completely. Combine milk, 2 tablespoons Kahlua, 1 teaspoon coffee granules, remaining 1 teaspoon vanilla, and pudding mix in a bowl; beat at medium speed of a mixer 1 minute. Gently fold in 1-1/2 cups whipped topping. Spread pudding mixture evenly over brownie crust. Combine remaining 1 tablespoon Kahlua and remaining 1 teaspoon coffee granules in a bowl; stir well. Gently fold in remaining 1-1/2 cups whipped topping. Spread whipped topping mixture evenly over pudding mixture. Garnish with chocolate curls, if desired. Serve immediately, or store loosely covered in refrigerator. Nonalcoholic Mocha Version: When making the pudding mixture, substitute 2 tablespoons 1% low-fat milk for the Kahlua. In the topping, omit the Kahlua, and dissolve the coffee granules in 1 tablespoon water. Note: Store remaining brownie mix in a zip-top heavy-duty plastic bag in refrigerator; reserved brownie mix can be used for another pie or to make a small pan of brownies. To make brownies, combine reserved brownie mix (about 2 cups), 1/4 cup water, and 1 lightly beaten egg white in a bowl. Stir just until combined. Spread into an 8-inch square pan coated with vegetable cooking spray. Bake at 350 degrees for 23 to 25 minutes.