St. Patrick’s Day Cookie Decorating with Rainbow Buttercream Frosting

A fun activity to do this St. Patrick’s Day: cookie decorating of course! I created this tutorial for making some colorful rainbow shamrock cookies which are sure to impress all ages.

This St. Patrick’s Day cookie decorating tutorial uses just a round cookie cutter. There is no need to go out and buy a shamrock cookie cutter, making it all the easier.

Find the full tutorial including the sugar cookie recipe and buttercream frosting recipe below.

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Part 1: Gathering the Supplies for St. Patrick’s Day Cookie Decorating

To decorate the cutest rainbow shamrock cookies, you will want to gather:

• 6 Icing bags
• One Wilton #5 tip – buy this at a bake supply store or even Walmart
• Circle cookie cutter, I used the largest sized one in this set – p.s. I use this set all the time, totally worth the purchase!
• Gel food dye for buttercream frosting in red, orange, yellow, and green
• Palette knife
• Parchment paper, permanent marker, paper towel, small cup, and scissors
• Ingredients for a crusting buttercream, find my crusting buttercream icing recipe here
• Ingredients for sugar cookie dough, find my no spread sugar cookies recipe here

Part 2: Baking the Cookies and Setting up Your Icing Bags

1. Roll, cut out, and bake your sugar cookies according to the recipe. You will be able to make about 18 sugar cookies with the recipe and cookie cutter linked above.
2. Make your buttercream icing and separate it into six bowls:
   • One bowl will contain about a cup & a half of frosting. Keep that bowl undyed.
   • The five remaining bowls will be equal in amount. Color one red, one orange, one yellow, one lime green, and one green. You can, of course, play around with which colors you want in your rainbow.
3. Set up your icing bags as follows:
   • Place the white frosting into an icing bag with the tip #5 in it. Place each of the remaining colors of frosting into their own icing bags and then cut the tip off of the bag. The hole should be about a 1/4″ in diameter, but it’s okay if it isn’t perfect.

Part 3: Decorating Rainbow Shamrock Sugar Cookies

Check out the video above and then check out the photo tutorial below.

1. Outline and fill in the circle cookies using the white bag of icing that has the tip #5 in it. Then, smooth the cookies with the palette knife.
2. Allow the cookies to form a slight crust.
3. While the cookies are forming the crust, draw some shamrock shapes onto a piece of parchment paper and then cut them out. It is helpful to reference the cookie cutter so you know what size the shamrock will be relative to the cookie.

   

   
4. Lay the shamrock parchment paper on the top of one cookie.

   

5. Squeeze blobs of frosting around the edges of the shamrock parchment paper in a rainbow pattern.
6. Smooth the colored frosting out with the palette knife, making sure to wipe the palette knife in between color changes. I was able to fit the red, orange, and yellow in one length of the palette knife, wipe that off, then smooth the yellow (again), lime green, and green together in another swipe.
   • Pro tip – wipe the knife off first into a cup, then completely wipe clean with a paper towel. You can use the cup of (discard) frosting to decorate some of the cookies as a rainbow by painting it on with the palette knife.
7. Pull the parchment paper away from the cookie to reveal the shamrock with the rainbow background. I found this easiest to do by grabbing the stem and pulling up. You can then use the palette knife to clean up the edges by running it along the edge of the cookie.
8. Repeat steps 4-7 for all of the cookies. It is best to have multiple shamrock parchment paper cut outs so you don’t have to wipe them down between every cookie.

So fun, right? I love how these cookies like way harder than they actually are to make. These are great for little ones to do as well, although the rainbows may be more smeared – but that’s okay! They can definitely have fun with the would-be-discard cup of rainbow frosting.

I’d love to know in the comments below, what activities do you typically do for St. Patrick’s Day?

Save the Tutorial for Decorating Rainbow Shamrock Cookies

Make sure to save this St. Patrick’s Day cookies tutorial! Use the image below to pin it to your St. Patrick’s Day party board on Pinterest. Alternatively, use any of the social share icons on the top of the page to share it to your favorite social media site.