In a large bowl, whisk together the flour, salt, baking powder, and cream of tartar. Set aside.
In a hand mixer, beat melted butter, granulated sugar, and cream cheese until fluffy (2–3 minutes).
Add egg yolk and vanilla extract, mixing until incorporated.
Add lemon zest and lemon juice. Mix until well blended.
Add the dry ingredients to the wet, mixing until a soft dough forms.
Load the dough into a spritz cookie press and press onto an ungreased baking sheet.
Bake at 350°F for 10–12 minutes until edges just begin to brown.
Make the Cranberry Puree
Combine 1 cup cranberries, 2 tablespoon sugar, and 2 tablespoon water in a saucepan. Simmer the cranberries over medium heat for about 10 minutes, or until they burst and soften.
Remove from heat and blend using a hand blender until smooth.
Strain through a fine mesh sieve to remove the skins.
Let the puree cool completely before using.
Make the Cranberry Buttercream
Beat butter until smooth and creamy (about 3 minutes).
Add cranberry puree and vanilla extract. Mix until combined.
Slowly add powdered sugar, one cup at a time, mixing between each addition.
Dice the fresh cranberries finely.
Fold them gently into the buttercream with a silicone spatula.
Transfer the buttercream into a piping bag fitted with a metal tip.
Assemble the Sandwich Cookies
Flip half of the cookies so the flat bottoms face up—these will be the base for the frosting.
Pipe or spread frosting on the flat side of each upside-down cookie.
Press another cookie on top to make a sandwich.
Optional: Dust tops with powdered sugar.
Notes
If the dough is too soft and sticking to the spritz cookie press, place the loaded cookie press in the fridge for 5–10 minutes before using.
Most spritz cookie press instructions recommend skipping parchment paper. But I always use it—I like to protect my baking sheets from permanent cookie marks, and it makes it so much easier to lift the cookies off after baking.