1Heat oven to 350°F (325°F for dark or nonstick pan). In small bowl or 2-cup measuring cup, mix topping and 1 tablespoon of the dry cake mix. In large bowl, stir together remaining dry cake mix, the butter and egg, using fork, until crumbly. Reserve 1 cup crumb mixture. Using a piece of plastic wrap on crumb mixture, press remaining mixture in bottom and 1/2 inch up sides of ungreased 9-inch square pan; remove wrap.
2Bake 12 minutes. Pour topping over crust to within 3/4 inch of edge. Sprinkle with reserved 1 cup crumb mixture.
3Bake 22 to 26 minutes or until light golden brown. Cool 10 minutes; loosen edges of crust with knife. Cool completely, about 50 minutes. Sprinkle with coarse salt. For bars, cut into 4 rows by 4 rows. Store covered.