In a large mixing bowl, cream together ½ cup of softened Kerrygold unsalted butter and 1 cup of sugar with a hand mixer on medium speed until light and fluffy, about 3-4 minutes.

Beat in 1 room-temperature egg and 1 teaspoon of vanilla extract until well combined. Gradually mix in ¾ cup of plain Greek yogurt until everything is fully incorporated.

In a separate bowl, whisk together 2 cups of all-purpose flour, 1 teaspoon of baking powder, ½ teaspoon of baking soda, and a pinch of salt.

Gently fold the dry ingredients into the wet mixture using a spatula, being careful not to overmix.

Wrap your cookie dough in plastic wrap and refrigerate it for at least 4 hours or overnight.

Once chilled, preheat your oven to 350°F (175°C). On a lightly floured surface, roll out the dough to about ½-inch thickness.

Place the cookie shapes on a baking sheet lined with parchment paper, spacing them about 2 inches apart. Bake for 10-11 minutes.

Allow the cookies to sit on the baking sheet for 5 minutes after removing them from the oven. Then, transfer to a wire rack to cool completely.

In a mixing bowl, beat together ½ cup of softened butter, 1 teaspoon of vanilla extract, and a pinch of salt. Gradually mix in 2 cups of powdered sugar.

Once the cookies are completely cool, generously frost each one with your creamy buttercream and sprinkle with colorful sprinkles.