Combine dry ingredients in bowl of mixer fitted with paddle attachment. Combine melted butter and water in separate bowl; add to dry ingredients along with eggs. Mix on low speed until combined. Mix on medium speed 1 to 2 min. or until well blended, scraping side of bowl as needed. Gently stir in 8 oz. cookie pieces and 4 oz. peanuts.
Line a half-sheet pan with parchment paper. Attach 2-inch-high frame inside pan. Pour batter into prepared pan, spreading evenly. Top with remaining cookie pieces and nuts.
Bake in 325°F standard oven 40 to 45 min. or until desired doneness. Cool completely in pan on wire rack. Remove frame and cut 4 x 5 into 20 pieces.