Preparation

• Heat oven to 350°F.
• Brush 1 Tbsp. butter evenly onto bottoms and up sides of 2 (9-inch) round pans. Cover bottoms of pans with parchment, then brush 1 Tbsp. of the remaining butter evenly onto parchment rounds.
• Add 1 Tbsp. cocoa powder to each prepared pan; gently shake pan to evenly coat bottom of pan with cocoa powder, then tap bottom of inverted pan to remove excess cocoa powder.
• Split regular OREO Cookies in half, leaving creme on one half of each cookie. Reserve creme-topped cookie halves for later use. Finely crush remaining cookie halves.
• Combine flour, salt, baking soda, baking powder and 1/2 cup cookie crumbs. Add coffee to 1 cup of the remaining cocoa powder in small bowl; stir until dissolved.
• Beat granulated sugar and oil in large bowl with mixer until blended. Add eggs; beat 2 to 3 min. or until light and fluffy. Blend in sour cream and 1 tsp. vanilla. Gradually beat in coffee mixture. Add flour mixture; beat just until blended.
• Pour batter evenly into prepared pans.
• Bake 30 to 35 min. or until toothpick inserted in centers comes out clean. Cool 10 min. Invert cakes onto wire racks; remove and discard parchment. Turn cakes over; cool completely.
• Combine powdered sugar and remaining cocoa powder. Beat remaining butter in large bowl with mixer until light and fluffy. Add powdered sugar mixture and remaining vanilla; mix well. Gradually beat in milk.
• Reserve 1/2 cup frosting for later use. Fill and frost stacked cake layers with remaining frosting.
• Split Mini OREO Cookies in half, leaving creme on one half of each cookie.
• Press large and small creme-topped cookie halves, creme sides up, into frosting around side of cake. Top each large cookie half with 1 of the plain mini cookie halves, securing pieces together with some of the reserved frosting. Add small dab of the remaining reserved frosting to center of each small cookie.
• Sprinkle remaining cookie crumbs onto plate around bottom edge of cake.