BEAT cream cheese and sugar with mixer until blended. Gently stir in 1-1/2 cups COOL WHIP; spread 2 cups onto bottom of plastic wrap-lined 8x4-inch loaf pan.
MELT 3 oz. chocolate. Add to remaining cream cheese mixture along with dry pudding mix and milk; beat until blended. Spread over cream cheese layer in pan. Refrigerate 4 hours.
MICROWAVE remaining chocolate and COOL WHIP in microwaveable bowl on HIGH 1 min.; stir until blended. Cool slightly.
INVERT dessert onto platter. Remove pan and plastic wrap. Top dessert with chocolate glaze and nuts. Refrigerate until glaze is firm.