In a small pot, combine the sugar, lemon juice, yolk, and lemon juice.
Cook over medium-low heat for 12 minutes, stirring constantly until the curd looks vibrant yellow and is thick enough to coat the back of a spoon.
Pour the curd into a bowl and stir in the butter.
Set aside to cool completely before using. Place it in the fridge to chill quickly!
In a large bowl, cream together the butter and cream cheese until combined.
Pour in the sugar and mix until fully combined and fluffy.
Mix in the egg, egg yolk, and vanilla.
Fold in the flour, baking powder, and salt until just combined.
Scoop with a standard cookie scoop (roughly two tablespoons) and drop each one into a bowl of powdered sugar.
Toss the ball in the powdered sugar until fully coated.
Transfer them to a parchment-lined baking tray.
Use the bottom of a tablespoon to press down the top of the dough to create a well, then fill it with one teaspoon of the lemon curd.
Freeze the cookies for 1-2 hours or until frozen solid. Then bake them 2-3 inches apart on a parchment lined tray at 350 F/180 C for 12-13 minutes.
Let them cool completely on a wire cooling rack then dust with more powdered sugar and enjoy!