1. Heat oven to 350 F. Grease 8 or 9-inch square baking pan. Remove wrappers from chocolates; chop 10 chocolates into 1/4-inch pieces. Set aside.
2. Beat butter, sucralose and vanilla until well blended. Gradually beat in flour. (Dough will be crumbly, but moist.) Stir in chocolate pieces. Pat dough into prepared pan.
3. Bake 30 to 35 minutes or until edges are lightly browned. Remove from oven; immediately cut into bars. Cool completely in pan on wire rack. Remove bars from pan; place on sheet of wax paper.
4. Place remaining 2 chocolates in small microwave-safe bowl. Microwave at MEDIUM (50%) 30 seconds; stir. If necessary, microwave at MEDIUM 10 seconds at a time, stirring after each heating, until chocolate is melted. Drizzle bars. About 24 bars.
*Such as Splenda, an artificial sweetener