These cute clam shell sandwich cookies are filled with colorful icing and even an edible pearl – they’re perfect for a beach-themed or mermaid party!

Clamshell Cookies

If you’re planning a mermaid party or an under-the-sea themed event, these adorable clamshell cookies are the perfect sweet treat for the occasion!

We started with a simple sugar cookie dough and shaped the cookies with a clam shell cookie cutter. They’re filled with buttercream frosting, topped with royal icing to really look like the surface of a clam shell, and there’s even an edible pearl inside!

Ingredients

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Cookie Ingredients:

• 3 cups all-purpose flour
• 1 tsp baking soda
• 1/2 tsp salt
• 1 cup unsalted butter (softened)
• 1 cup granulated sugar
• 1 egg

Buttercream Frosting Ingredients:

• 1 cup butter (softened)
• 2 cups powder sugar
• 1 tsp vanilla extract
• 1 tsp heavy whipping cream
• 2 drops of pink food coloring

Royal Icing Ingredients:

• 2 egg whites
• 1 cup powdered sugar
• 1/2 tsp cream of tartar
• 1 tsp vanilla extract

Supplies

• Electric Mixer (or stand mixer)
• Cookie Sheet 
• Parchment paper or Silicone Baking Mats
• Piping Bag
• Clam Shell Cookie Cutter
• Edible Pearls (for decorating the cookies)

Instructions

For the “shortcut version” of this recipe, you can skip the royal icing and save 2-3 hours of time.

To Make The Cookie Dough:

1. Cream the soft butter with the sugar until the combination is smooth not grainy to the touch in a mixing bowl.
2. Add eggs and vanilla and continue to mix.
3. Sift the four, baking soda, and salt together. Add the dry ingredients to the bowl of wet ingredients and mix until well incorporated.
4. Form the dough into a ball, wrap it in plastic wrap, and place in the refrigerator for about 6 hours, or overnight.

To Bake The Cookies:

To Prep: Preheat oven to 325 degrees Fahrenheit and line a cookie sheet with parchment paper or a non-stick silicone baking mat.

1. Take the cookie dough out of the refrigerator and allow to sit out for a few minutes at room temperature, to soften slightly.
2. Roll the dough out on a floured workspace and begin making cookies with the cookie cutter.
3. Use a spatula to transfer the the cut cookies to the prepared pan and bake for 8 minutes at 325 degrees.
4. Remove from oven and transfer cookies to a wire rack to finish cooling.

To Make The Royal Icing:

1. Combine all ingredients in the bowl of a stand mixer (or a large bowl using an electric mixer).
2. Mix on medium speed until stiff peaks form (about 5 minutes). If the icing looks a little too runny, add another 1/2 cup of powdered sugar.
3. Scoop some icing into the piping bag and the rest into the bowl
4. Add a tablespoon of water to the bowl and mix, to thin the icing a bit, then pour into a squeeze bottle.
5. Set half of the baked clam shell cookies aside, as those will be the bottom half of each cookie sandwich. Take the other half of the cookies to decorate with the royal icing.
6. Outline your cookies using the white icing in the piping bag, then use the thinner icing in the squeeze bottle to fill in the surface of the cookies. Allow to dry for 1 hour.
7. Use the piping bag again to add lines to the clam shells, then allow to dry for another hour.

Buttercream Frosting Directions:

1. Using a standing mixer, blend all frosting ingredients, except the food coloring, until well combined and stiff peaks form.
2. Once your frosting comes together, add the food coloring and mix until smooth.
3. Scoop the frosting into a piping bag with star tip.
4. Pipe on the pink frosting onto the bottom (undecorated) clam shell cookie.
5. Take one of the decorated shell cookies and gently press on top of the pink frosting to form a cookie sandwich. Place one pearl candy decoration on the icing, inside the cookie, so you can see it.

Prep Tips

• Yield – The amount of cookies will depend on the size of your cookie cutter. You should be able to make at least 12-18 sandwich cookies, unless you are using a very large cookie cutter.
• Shortcut Recipe – We used royal icing to decorate the tops of our cookies so they really look like a clam shell. However, royal icing takes a couple hours to dry, so if you want to save time, you can skip this step and leave the tops of the cookies unfrosted. They will still look like clam shells and be super tasty, and they will be much faster to make.

More Beach and Ocean Themed Recipes

• Shark Lollipops
• Pirate Flag Cookies
• Surfboard Cookies
• Starfish Cookies

Clam Shell Cookie Recipe (Printable Recipe Card)

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