Bake cake. Prepare three white cake mixes, separately, following recipe instructions. Using Pink icing color, tint two prepared cake mix batters pink.
Toss ½ cup chocolate chips in one tablespoon flour. Add to one of the pink batters. Repeat with remaining chocolate chips and flour. Add to second pink batter.
Tint remaining prepared cake mix batter green using color combination provided. Combine Kelly Green, Leaf Green and Lemon Yellow icing colors to get green cake batter color shown.
Bake and cool two pink cakes and one green cake, filling pan 2/3 full. Trim each layer to 2 in. high.
Make seeds. Melt 4 oz. Black Candy Melts candy according to package instructions.
Prepare decorating bag with melted black candy; cut ¼ in. off tip of bag.
On waxed paper-covered cake board, pipe seeds. Chill until set, about 10 minutes.
Tint icing. Tint 1¼ cup white icing pink using color combination provided. Combine Christmas Red and Pink icing colors to get pink icing color shown. Reserve remaining icing white.
Prepare two decorating bags, separately, with tip 1A. Prepare one bag with pink icing, the other with white.
Assemble cake layers. Place small amount of icing on 6 in. cake board. Place green cake on board.
Using bag with white icing, ice top of green cake layer. Stack pink layer on top of green layer.
Using bag with pink icing, ice top of pink cake layer. Stack remaining pink layer on top of previous pink layer.
Using remaining white icing and spatula, ice sides of cake smooth, leaving top of cake un-iced. Chill until set, about 20 minutes.
Prepare sanding sugar. On long edge of pan, sprinkle horizonal line of dark green sugar, at least ¼ in. thick and measuring ¾ in. wide. Repeat with light green sugar, making a line 1¼ in. wide. Repeat with granulated sugar, making a line about ½ in. wide. Repeat with pink sugar, making a line about 4½ to 5 in. wide (1 cup).
Helpful Hint: Using the icing smoother to help keep your sugar lines straight.
Decorate cake. Place small amount of icing on 6 in. board; attach to top of cake.
Holding hands on both sides of cake boards (top and bottom), line up bottom edge of cake with dark green sugar and roll cake forward, keeping cake on bottom edge of dark green sugar as you roll. Once complete, pick up cake and re-roll sections not covered in sugar.
Place cake on surface; carefully remove top cake board.
Prepare decorating bag with remaining white icing. Cut ¼ in. off tip of bag. Pipe icing on top of cake. Carefully smooth using spatula. Top with remaining pink sanding sugar.
Using small amount of icing, attach candy seeds to pink section of cake.