Tender soft sour cream lemon cookies with luscious lemon curd baked right in. These are perfect for any time of the year and are a true taste of sunshine!
Combine flour, baking powder, baking soda and salt in a large bowl and whisk to blend evenly.
Combine soft butter, sugar, lemon zest and vanilla in a large bowl and beat with an electric mixer for 2 minutes until pale and fluffy. Beat in egg until evenly incorporated. Mix in sour cream. Add the flour mixture and fold it in by hand with a spatula until it is just combined.
Transfer the sticky dough to a piece of plastic wrap, flour your hands and carefully shape it into a 10-12 inch log. Wrap it well and refrigerate for 2 hours.
Preheat your oven to 375°F (NOTE: you will not bake at 375 for the whole time. You will need to lower the temperature to 350 after 3 minutes). Line two large cookie sheets with parchment paper.
Slice the log into 18 equal portions and roll each one into a smooth ball. Roll each ball in granulated sugar and then roll in powdered sugar until evenly coated. Place dough balls onto cookie sheets leaving at least 3 inches of space between them as they spread quite a bit.
Use a round ½-teaspoon measuring spoon to make an indent into the center of each dough ball. When you press the indent into the dough balls for filling with lemon curd, use one hand to gently press it together to keep it from cracking as you press the spoon in to make the indent. If it cracks, simply press and shape it back together with your fingers. Fill the indent with a heaped teaspoon of lemon curd. Bake for 3 minutes, then lower the temperature to 350°F and bake for another 10 minutes until cracked and just lightly golden around the edges and the lemon curd looks matte.
Let cookies cool for 2 minutes on the baking sheets, then transfer them individually to a wire rack to cool completely. Dust with icing sugar once they are cooled and serve!