Beat 2 eggs, 1/3 cup water, 1/4 cup soft butter, 1/4 cup crunchy peanut butter, 1/2 package of yellow cake mix, until light and fluffy. Stir in rest of cake mix and 6 ounces of chocolate chips. Stir in 1/2 cup chopped nuts. Dough will be stiff. Spread in greased 10 1/2 x 15 1/2 inch pan. Bake at 350 degrees for 25 to 30 minutes. Take out of oven and sprinkle 6 ounces of chocolate chips. Let stand 5 minutes to melt. Spread all over cake batter. Mix 1/2 cup sifted confectioner's sugar, 1/2 cup peanut butter, 2 to 4 tablespoons evaporated milk. Drizzle over melted chocolate on cake. With fork, make lines up and down and across. Cool. Cut into 3 x 1 1/2 inch bars. Makes about 30.