Preheat your oven to 350 degrees Fahrenheit. Line baking sheets with parchment paper.
In a large bowl, beat the softened butter and cream cheese together until smooth.
Gradually add 1 1/2 cups of powdered sugar to the butter mixture and beat until light and fluffy.
Mix in the vanilla extract, lemon zest, and lemon juice until just combined.
In a separate medium bowl, whisk together the gluten-free flour blend, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing on low speed until a soft dough forms. Do not overmix.
Scoop the dough using a small cookie scoop (about 1 tablespoon size) and roll into smooth balls. Place them 2 inches apart on the prepared baking sheets.
Bake for 10 to 12 minutes, or until the edges are set but the centers remain pale. The cookies will look soft.
Remove the sheets from the oven and let the cookies cool on the sheets for 5 minutes before transferring them to a wire rack to cool completely.
Once completely cool, place extra powdered sugar in a shallow bowl. Roll each cookie generously in the powdered sugar until fully coated. For a thicker coating, you can roll them a second time after the first layer sets slightly.
Notes
Use a high-quality 1-to-1 gluten-free flour blend that contains xanthan gum for the best texture.
Chill the dough for 30 minutes if your kitchen is warm, as this helps the cookies hold their shape during baking.
For an extra intense lemon flavor, add 1/4 teaspoon of lemon extract along with the vanilla.