1Heat oven to 350ºF (325ºF for dark or nonstick pan). Grease bottom only of 13x9-inch pan with shortening or cooking spray. Make brownie batter as directed on brownie box--except stir 2 teaspoons instant coffee granules into batter. Spread batter in pan.
2Bake as directed on brownie mix box. Cool completely, about 1 1/2 hours.
3In medium bowl, dissolve 2 teaspoons instant coffee granules in hot water. Mix in remaining frosting ingredients with electric mixer on low speed until combined; increase speed to medium and blend until light and fluffy. Spread frosting over brownies.
4In small microwavable bowl, place chocolate chips and shortening. Microwave on High 30 to 45 seconds; stir. Drizzle over frosting. For 24 brownies, cut into 6 rows by 4 rows. Store tightly covered.