Heat oven to 350°. Beat butter and sugar in large bowl with mixer until light and fluffy. Add dry pudding mix; beat until well blended. Add eggs and baking soda; mix well. Gradually add flour, beating after each addition until well blended. Stir in chocolate. Drop tablespoons of dough, 2 inches apart, onto baking sheets. Bake 10 to 12 min. or until edges are lightly browned. Cool 1 min. on baking sheets; remove to wire racks and cool completely.