Creating these delicious Key Lime Cookies is straightforward when you follow these steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
2. Mix Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt.
3. Cream Butter and Sugar: In a large bowl, beat the softened butter and granulated sugar together until light and fluffy.
4. Add Egg and Flavorings: Incorporate the egg, key lime juice, lime zest, and vanilla extract into the butter mixture, mixing until well combined.
5. Combine Mixtures: Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
6. Form Cookies: Using a cookie scoop or tablespoon, drop dough onto the prepared baking sheet, spacing them about 2 inches apart.
7. Bake: Place in the preheated oven and bake for 10-12 minutes, or until the edges are lightly golden.
8. Cool: Remove from the oven and let the cookies cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.
9. Dust with Powdered Sugar: Once cooled, dust the cookies with powdered sugar for an extra touch of sweetness.

By following these steps, you’ll have delicious Key Lime Cookies that are sure to delight!