Preheat oven to 350oF. Lighlt grease an 8" square pan. In small saucepan, melt 1/4 c butter or margarine and chocolate over low heat. Set aside. In medium bowl, beat eggs until light. Beat in sugar, flour, salt and vanilla until blended. Stir in melted chocolate mixture; pour batter into prepared pan. Bake for 15 minutes. Meanwhile, prepare Caramel Sauce. In small saucepan, mix butter or margarine and brown sugar. Bring to boil, stirring constantly. Stir and simmer 1 minute. Remove brownies from oven and sprinkle evenly with pecans. Gently pour caramel sauce over brownies. Return pan to oven and bake 15 minutes longer, until caramel is bubbling. Remove brownies from oven and sprinkle with chocolate chips. As chocolate chips begin to melt, gently swirl with a knife. Cool completely before cutting. Chill to harden chocolate, if necessary. Source: Marian Hoffman, Whitmans Chocolate Cookbook.