Once the cookies are finished baking, remove them from the oven and cool them for 2 minutes on the cookie sheets and then remove to cooling racks that are sitting over sheets of parchment paper or plastic wrap.
Using a small child's spoon, spoon a small amount (about ½-1 teaspoon depending on the size of your divot) into each cookie being careful not to get any on the sides of the cookie.
Using a sugar shaker or fine mesh strainer, lightly sprinkle confectioners sugar over each cookie. You don't want it to cover the curd completely or you won't be able to see that it's a lemon cookie.
To store, place in a large, shallow container. The cookies will keep up to two weeks (if they last that long) and can be frozen. I sometimes make the cookies and freeze them unfilled and make the curd before serving. The cookies can stick together which makes stacking them a challenge.