Heat oven to 350°F. Lightly spray 13x9-inch pan with Crisco® Original No-Stick Cooking Spray.
In medium bowl, stir brownie mix, oil, water and eggs 50 strokes with spoon. Spread batter in pan; set aside.
In large bowl, beat cream cheese with electric mixer on medium speed until fluffy. Add milk and peanut butter; beat until smooth. Stir in 1 cup of the toffee bits. Spoon mixture over batter; spread evenly.
Bake 30 to 40 minutes or until cheesecake layer is set and edges are light golden brown. Cool on cooling rack 30 minutes. Refrigerate 40 minutes.
In small microwavable bowl, microwave chocolate chips and cream uncovered on High 40 to 60 seconds or until chips are melted; stir until smooth. Spread over cheesecake layer. Sprinkle with remaining toffee bits. Cool completely, about 1 hour. For brownies, cut into 6 rows by 6 rows. Store covered in refrigerator.