bottom layer: prepare first box of brownie mix as directed on the box. Preheat oven to 350 degrees. Grease a 13x9-inch baking dish. Spread the brownie batter evenly into the greased pan.
filling: using an electric mixer, beat together the cream cheese, egg and sugar until smooth. Spread cream cheese mixture over top of the brownie batter.
top: prepare second box of brownie mix as directed on the box. Spread over cream cheese layer evenly. Bake in a 350 degree oven for 35 to 37 minutes. Brownies will be done when a toothpick inserted in center comes out clean. Cool in pan, then cut into bars or squares and serve. Keep refrigerated.