The secret firecrackers in these soft and chewy cookie bars come from a layer of Pop Rocks up top. Pop Rocks are on the safe list for kids who have peanut and tree nut allergies, which is great because Eva loves them! I love that they just look like sprinkles on these bars – definitely a surprise for anyone who doesn’t see that little *pop pop pop* coming! Note: the blue pop rocks were pretty green in person, as you can see on our Mickey Mouse Firecracker Cookies, so I elected to stick with only the red Pop Rocks for these cookie bars.
For the cookie bars:
1/2 cup softened butter
3/4 cup sugar
1 large egg and 1 egg yolk
2 teaspoons vanilla extract
1 and 1/2 cups all-purpose flour
1/4 teaspoon salt
1 teaspoon baking powder
1/2 teaspoon baking soda
1 and 1/2 teaspoons cornstarch
Red, white, and blue sprinkles (Use the chunky kind or they’ll just melt away and dye your cookies a weird color! I used fat stars for these ones.) – Be sure to check for nut allergy warnings!
For the frosting:
3/4 cup butter
2 and 1/2 cups powdered sugar
3 Tablespoons heavy cream
1 teaspoon vanilla extract
A pinch of salt
Star sprinkles and/or blue sugar crystals for the frosting (optional) – be sure to check for nut allergy warnings!
Preheat oven to 350F degrees. Line an 8-inch or 9-inch square baking pan with aluminum foil, making sure to leave enough overhang on the sides. Set aside.
In a large bowl using a stand mixer fitted with a paddle attachment, cream the butter for about 1 minute on medium speed. Add the sugar on medium speed until fluffy and light in color. Beat in egg, egg yolk, and vanilla. Scrape down the sides as needed.
In a separate bowl, whisk together the dry ingredients. With the mixer running on low speed, slowly add the dry ingredients to the wet ingredients. Once combined, gently fold in the chunky sprinkles using a rubber spatula (or by mixing on low speed).
Pour into the baking pan and use a spatula to smooth it out to the edges. Bake for 25-26 minutes or until very lightly browned on top. Allow the bars to cool completely on a wire rack at room temperature before frosting.
Using your stand mixer again, beat the butter on medium speed for 2 minutes. Add the powdered sugar, cream, and vanilla extract with the mixer running on low. Increase to high speed and beat for 3 full minutes. Add more powdered sugar if frosting is too thin or more cream if frosting is too thick. Add a pinch of salt if frosting is too sweet. Beat in food coloring, if using. I added blue sprinkles to the cookies pictured above.
Once the bars are cooled, remove them from the pan and frost. Add the Pop Rocks to the top, along with any additional sprinkles you might be using, and cut the cookies into squares using a clean sharp knife. They’ll be a little soft, so put them into the refrigerator if you’re planning on taking them anywhere.
Enjoy and have a safe and happy 4th of July!!