With as many ways as there are to decorate cupcakes, they can be really boring if you just slap some plain icing on them. I like to make them fun and interesting, and one of my favorite ways to do that is with colorful, swirled icing.

Rather than mix food coloring into the icing, I use it to paint the decorator bag, creating a result so crazy and cool that you won’t believe you got it from such a simple technique. Let me show you how!

Gather the supplies

The first things you’ll need, of course, are cupcakes and icing! This technique works best with white decorator’s icing (see here for my recipe), but you can use canned frosting if you need to, just make sure it’s as white as possible. As for equipment, you’ll need some disposable icing bags, a star-shaped icing tip (I like size 18), and optionally a coupler. You’ll also need a small, clean paint brush and some paste food coloring in various colors. (It must be paste. Liquid won’t work.) Finally, grab a tall drinking glass, which will help to hold the bag for you.

Select the colors

The best part about this technique is that you can choose any colors you want and can customize it to the occasion. You can use orange and black for Halloween, red and green for Christmas, or pink and blue for a baby shower. A rainbow of colors makes for a fun child’s party treat (like Jo’s Candyland party) and can even look tie-dyed. Using team colors will make a great addition to any sporting event, from a child’s soccer game to a tailgating party.

You’ll be painting from 4 to 6 stripes of color for your icing, but you can repeat colors, so you really only need at least 2 different colors (up to 6 max).

Paint the bags

Okay, now for the actual technique! Attach the star tip and coupler to the disposable bag and flip the end of the bag out to form a cuff, so that you can reach the inside easier. Here’s where the glass comes in handy, as it serves as a holder for the bag. Put the tip of the bag in the bottom of the glass and let it stand upright.

Now use the paint brush to paint stripes of color on the inside of the bag, starting at the tip and going up about 3-4 inches. Each stripe of food coloring should be fairly thick and about 1/2″ wide.

If you are using 2 or 3 colors, paint two stripes of each color, alternating them. If you are using 4, 5, or 6 colors, paint one stripe of each color. Be sure to leave some space between each stripe.

The photo on the left shows me painting orange and black alternating stripes, and the result is in the center photo. On the right, you can see a rainbow of 6 colors (red, orange, yellow, green, blue, and purple).

Fill the bags

Now scoop a bunch of white icing into the bag with a spoon. The stripes of color will be very easy to see now. Twist the top of the bag to close it and squeeze icing out of the tip until it no longer flows white, but starts to show the colors you used. Pretty cool, huh?

Decorate the cupcakes

Now for the fun part! Squeeze the icing out onto the cupcake in any design or pattern you want. Here are some example patterns I like:

The results

Here are my finished cupcakes. You can see that the color starts out bolder and fades as you do more cupcakes. Eventually you’ll run out of icing in the bag, but unfortunately you can’t just keep adding more, because your color will get all used up. You’ll need to start with a clean bag each time you need more icing (which is why I like the disposable ones) and paint fresh stripes on it. You should be able to get about a dozen cupcakes out of one bag of icing.