These cookies are excellent, with just enough tartness from the lemon zest and juice plus the apricot preserves to compliment the sweetness of the confectioner sugar on top.
In a large bowl, add flour and baking powder (either measured or weighed) whisk through to blend. Set the bowl aside.
Add butter, granulated sugar, and cream cheese into a mixer bowl and blend until all is incorporated. I mix for 3 minutes on medium speed. Beat in egg, then add in lemon juice and lemon zest.
Slowly add your flour mixture and blend till just incorporated. Cover and put into the refrigerator for at least an hour.
Line 2 cookie sheet pans with parchment paper. Roll a teaspoon of dough to make a ball about 1-½ to 2 inches in circumference. Using your thumb, go about ¾ of the way through the ball. Fill the hole with apricot preserves.
Bake at 350°F (175°C or 180°C) for 11-13 minutes. I touch the top of the cookie, and if it seems slightly firm, I pull them out of the oven. They should have a light golden brown bottom. Move to a cooling rack to cool. When cooled, sprinkle with confectioner sugar.
Notes
As a side note, I did not add salt to this recipe, but you can certainly add ½ teaspoon of salt or use salted butter.