In a microwavable bowl or double broiler, melt together chocolate chips, sweetened condensed milk and two tablespoons butter. Set aside.
To make dough, in a two-quart saucepan over medium heat combine melted butter and brown sugar. Mix until brown sugar is dissolved and remove from heat. Add to saucepan flour, salt, vanilla, chopped nuts, flaked coconut and eggs. Mix well. Spread half of dough mixture in a 15 x 10-inch jelly roll pan greased with non-stick spray. Drizzle melted chocolate mixture over dough in pan. Dot top of chocolate mixture with remaining dough.
Bake at 350 F for 30-40 minutes or until golden brown and set in the middle. Cool well on a wire rack for one or two hours. Cut into 48 bars. Store tightly covered.