Add eggs one at a time then the vanilla extract while mixing on low, scrape the bowl down.
On low, mix in flour, cornstarch and salt.
Separate dough into two parts. Wrap in plastic and chill for about an hour.
Roll out between two pieces of parchment paper.
Roll to between ½ and 1/4 inch thickness.
With a cookie cutter, cut out star shapes.
Place stars on a baking sheet lined with parchment paper.
Bake for about 12 minutes.
Allow cookies to cool on their baking sheet until room temperature.
For the Buttercream:
Cream the butter If you're using a stand mixer you'll want the paddle attachment for this part.
Sift in half the confectioner’s sugar and mix on low. Scrape the bowl down and sift in the remaining sugar then mix once more.
Add the vanilla and then the cream a tablespoon at a time. Beat until you have an even, fluffy consistency. Mix in food coloring until you have the desired color.
Transfer to a piping bag fitted with a size 30 star tip.
For the Assembly:
Use the buttercream as glue between each layer.
Start by piping buttercream to the bottom of a medium sized star.
Place star in the middle of a cake stand and press.
Alternate sizes between small and large stars to create a layered look to ascends into a tree. Save a small star for the tree topper.
Once you’re finished stacking, pipe buttercream onto each branch.
Add ornament decorations. I used Christmas color chocolate balls to decorate with. Dust with powdered sugar for a snowy effect.
For the Star:
Mix milk and powdered sugar together to create a glaze.
Paint the glaze onto the cookie using a paintbrush.
Place a sheet of gold leaf over the the cookie.
Flatten with brush and smooth out.
Pipe buttercream to the top star.
Place gold star as the tree topper.
Video
Notes
The dough only needs to be chilled for about 20-30 minutes. Just until it's firm enough to cut and handle without marring the edges.
The different sized stars will bake for different times so bake the large ones on separate cookie sheets so they can come out later.
If your butter isn’t room temp just cut the sticks into a few slices and microwave on 50% power in 5 second bursts. Flip the butter with every burst.
Measure your flour correctly! Adding too much flour to the recipe is the most common mistake. The best, and easiest way to measure flour is by using a scale. If you don’t have one then fluff your flour with a spoon, sprinkle it into your measuring cup, and use a knife to level it off.
Scrape your bowl down a few times. If you have a glob to two of butter that doesn’t get mixed with the flour it will loose shape and melt when baked.
Use a high-quality vanilla if you can. Aside from the butter it’s the main flavor you’ll taste and worth the splurge!
I used a good amount of green food coloring for the buttercream but you can get a nice soft green by using matcha powder to color and flavor the buttercream.
You might need to let your buttercream set for a while after building the tree and before covering the tips of the stars in buttercream and decorations.
If you can's find the mini chocolate spheres I used for the ornaments try other smaller candies like M&Ms or even crushed candy canes.