Make turrets one day in advance. Use a knife to cut dowel rods to the following lengths: 8 1/2 in. (two), 4 in. (two) and 3 in. (one).
For turret peaks, use a knife to cut a mark in sugar cones to the following lengths starting at tip of cone: 2 1/2 in. (two) and 2 1/4 in. (three). Soften cone by dipping wide end of cone into glass of water to marked heights. Remove. Use knife to trim marked heights. Let dry.
Tint 3 oz. fondant rose. Use fondant roller with purple guide rings to roll out fondant 1/8 in. thick. Use brush to cover dried sugar cones with piping gel. Cut three strips, each 3 in. high x 4 in. high. Cover cones with fondant strips; trim off excess. Reserve remaining fondant.
Melt white Candy Melts candy according to package directions. Use parchment bag and melted white candy to outline rim of dowel rod. Attach turret peak to dowel rod. Chill until firm.
For turret windows, tint 2 oz. fondant violet. Use fondant roller and pink guide rings to roll out fondant 1/16 in. thick. Use knife and patterns to cut out four medium windows and three small windows. Reserve remaining fondant. Use brush and piping gel to attach windows to turrets.
Make 20 cupcakes. Prepare cupcake batter following recipe. Bake and cool cupcakes. Prepare buttercream icing. Tint rose. Use spatula and tinted icing to ice cupcakes smooth.
Assemble cupcakes: six cupcakes for the first two bottom rows, five cupcakes for the third row, two cupcakes for the fourth row and one cupcake for the fifth row.
Make castle windows and door. Use fondant roller and pink guide rings to roll out reserved fondant 1/16 in. thick. Use knife, pattern and rose fondant to cut one medium window. Use knife pattern and violet fondant to cut door, two medium windows and three large windows. Place pieces in storage board until ready to use.
Decorate turrets. Insert smallest turret into top cupcake leaving 2 in. extended. Use tip 4 and rose icing to outline windows. Attach Sugar Pearls.
Make leaves. Tint 2 oz. fondant green. Use fondant roller and pink guide rings to roll out fondant 1/16 in. thick. Use small leaf Cut-Out to cut 35-40 leaves. Place in storage board until ready to use.
Decorate castle. Use tip 4 and rose icing to pipe drop strings, 1 1/4 in. wide x 3/4 in. deep, on top portions of cupcakes. Attach Sugar Pearl at each end of drop strings.
Use damp brush to attach rose fondant window to door. Use damp brush to attach windows and door onto cupcakes. Use tip 4 and rose icing to outline windows and door; attach Sugar Pearls.
Position remaining turrets. Use icing to attach turrets to cupcakes. Use damp brush to attach leaves.
The drop string is traditionally used as decoration on the sides of the cake and is the basis of more ornate string work. Called a "drop" string because the line of piped icing is allowed to "drop" or fall, by itself, before reattaching it to your cake. Pipe a row of single strings or multiple strings in rows of two or three.