One day in advance, pipe message. Prepare Royal Icing recipe to stiff consistency following recipe instructions.
Place Happy Birthday template on cake board; cover with parchment paper.
Prepare 12 in. decorating bag with tip 5 and royal icing. Following template, pipe four ‘Happy Birthday’ messages (three will go around the cake, one is just in case of breakage).
Allow to dry 8 to 10 hours, or overnight.
Bake cake. Prepare cake batter following recipe instructions. Bake and cool three cake layers. Level, fill and stack layers for 6 in. high cake. Place cake on cake board.
Crumb coat cake. Chill until set, about 1 hour.
Tint icing. Prepare six bowls each with 2 cups white icing. Tint one portion each orange, green, blue and purple using color combinations provided. Combine Orange and Lemon Yellow icing colors to get orange color shown. Combine Lemon Yellow and Leaf Green icing colors to get green color shown. Combine Royal Blue and Rose icing colors to get blue color shown. Combine Violet and Rose icing colors to get purple color shown.
Using Pink icing color, tint one portion pink. Using Teal icing color, tint one portion teal.
Reserve remaining icing white.
Pipe lines on cake. Prepare seven 12 in. decorating bags with couplers and tip 10. Fill separately with orange, green, blue, purple, pink, teal and white icing. Reserve bowls for later step.
Using a ruler and toothpick, mark a line around the cake 3¼ in. from the bottom. Do the same 4½ in. from the bottom of the cake. This marks where the colored stripes will appear on your cake.
Helpful Hint: Use the ruler to mark ½ way between the two marked lines (approx. 3 7/8 in.). This is where the center of your rainbow bar will be.
Starting at the bottom of the cake, use bag with white icing to pipe continuous lines from the bottom of the cake up to the first marked line.
Switch to purple icing. Pipe one line around entire cake. Repeat with blue, teal, green, orange and pink icing.
Reserve tinted icing in bags.
Switch back to bag with white icing. Pipe continuous lines to the top of the cake.
Ice and smooth top of cake. Using icing smoother, carefully smooth sides of cake, wiping icing from smoother after each use.
Chill cake until icing is set, about 2 hours.
Ice cake. Prepare 16 in. decorating bag with tip 789 and white icing. Pipe even strips of icing around cake, starting at bottom and stopping at the purple line of icing. Leave the striped bar un-iced and continue piping icing around the cake until you get to the top.
Using an icing smoother, smooth icing, being careful not to apply too much pressure. Using a 9 in. tapered spatula, correct any icing that may have spread into the rainbow bar.
Smooth top of cake.
Pipe borders. Switch purple, blue, teal, green, orange and pink bags to tip 2. Alternating colors, pipe one row of arrows, approx.. ½ in. to ¾ in. high, pointing left, then another row of arrows pointing right, making sure to align colors.
Squeeze remaining icing back into individual mixing bowls.
Prepare six 12 in. decorating bags with tip 1M. Fill separately with remaining purple, blue, teal, green, orange and pink icing.
Alternating colors, pipe tight rope border around top edge of cake.
- Decorate cake. Carefully remove royal icing letters from parchment paper. Place letters around cake, resting on edge of fault line, away from striped area (three complete ‘Happy Birthday’ messages should fit around your cake).
Beginner
