Preheat oven to 350°. Whisk together flour, baking powder, and salt. Beat brown sugar and butter at medium speed with an electric mixer until fluffy. Add eggs, 1 at a time, beating until blended after each addition. Add vanilla, beating until blended. Gradually add flour mixture, beating at low speed just until blended. Stir in milk chocolate morsels just until combined. Spread batter in a lightly greased 8-inch square pan. Microwave caramel bits and cream in a microwave-safe bowl at MEDIUM (50% power) 2 minutes or until melted, stirring at 30-second intervals. Pour caramel mixture over batter, and gently swirl with a knife. Bake 35 to 40 minutes or until a wooden pick inserted in center comes out clean. (Center will rise and fall while baking.) Cool completely in pan on a wire rack (about 1 hour) before cutting.