1. Heat oven to 350°F. Grease 13x9x2-in. baking pan.
2. Place baking chocolate and butter in large microwave-safe bowl. Microwave at MEDIUM (50%) 2 to 2-1/2 minutes, stirring after each minute, until mixture is melted. Beat in 2 cups sugar, 3 eggs and vanilla until blended. Stir in flour; spread batter in prepared pan.
3. Beat cream cheese, remaining 1/2 cup sugar and remaining 1 egg; stir in 1-1/4 cup chocolate pieces, cherries, almond extract and red food color, if desired. Drop by spoonfuls over top of chocolate mixture in pan.
4. Bake 35 to 40 minutes or just until set. Remove from oven; immediately sprinkle remaining 1/2 cup chocolates over top. Cool completely in pan on wire rack; cut into bars. Cover; refrigerate leftover bars. Makes 24 to 36 bars.