Microwave chocolate squares in a microwave-safe bowl at MEDIUM (50% power) 1 1/2 minutes, stirring at 30-second intervals until melted. Stir until smooth.
Beat butter and sugar at medium speed with an electric mixer until light and fluffy. Add eggs, 1 at a time, beating just until blended after each addition. Add melted chocolate, beating just until blended.
Add flour, beating at low speed just until blended. Stir in vanilla and chocolate morsels. Spread batter into a greased and floured 13- x 9-inch pan. Sprinkle batter evenly with coconut, 1 (12-ounce) package semisweet chocolate morsels, and chopped pecans. Drizzle evenly with sweetened condensed milk.
Bake at 350° for 50 to 55 minutes or until golden brown and center is set. Cool completely on wire rack. Cut into squares.