Piping bag

A piping bag is a cone-shaped bag made of plastic, silicone or coated fabric. You fill it with a soft mixture and squeeze it out through the narrow end, often through a metal or plastic tip called a nozzle. It lets you pipe frosting onto cakes, shape meringue and choux pastry, fill doughnuts and form even cookies. In the UK it is often called an icing bag.

How to do it

1. If you use a tip, cut the end of the bag so the tip pokes through about halfway, then drop it in.
2. Twist the bag just above the tip and push the twist into the tip. This keeps the filling from leaking while you fill it.
3. Stand the bag in a tall glass and fold the top down over the rim like a cuff.
4. Spoon in the mixture until it is half to two-thirds full.
5. Unfold the cuff, push the filling down toward the tip and twist the top closed.
6. Untwist the tip end. Hold the twisted top in your dominant hand and squeeze from there. Use your other hand only to guide the tip.
7. Stop squeezing before you lift the tip away, so each shape ends cleanly.

Common tips:

• Round for choux, meringue kisses and writing.
• Open star for rosettes and swirls on cupcakes.
• Closed star for deep ridges on cookies and frosting.

Substitutes

A strong zip-top freezer bag with one corner cut off works for simple shapes and filling. A small cone of parchment paper works for writing with chocolate.

Common mistakes

• Overfilling the bag. It is hard to control and leaks out the top.
• Squeezing from the middle of the bag. Filling squirts out of the top.
• Cutting the end too wide, so the tip falls out.
• Holding the bag too long in a warm hand. Buttercream and ganache melt and lose their shape.
• Leaving air pockets. They make the mixture sputter.

In recipes

"Pipe" or "spoon into a piping bag fitted with a 1 cm (1/2 in) plain tip" tells you the tip shape and the size of the opening.