Fleur De Lis
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Formerly a symbol of the royal coat of arms of France, this impressive decoration is now generally synonymous with anything French. The swirled shells represent a lily.
Step 1: Shell Center
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Using tip 21 with medium consistency icing, position bag at 45° at 6:00, hold the tip slightly above the surface. Pipe a basic shell, elongate the tail.
Keeping the bag at a 45° angle, pipe a reverse shell to the left of the center shell and join the tails.
Repeat procedure to the right side of the center shell.
(Src : www.BakeDecorateCelebrate.com )