Preheat the oven and prepare a baking sheet.

In a saucepan, combine whole milk, unsalted butter, granulated sugar, and kosher salt; bring to a boil.

Stir in all-purpose flour until a dough forms; cook for a few minutes until it pulls away from the sides of the pan.

Remove from heat and let cool slightly before adding beaten eggs, one at a time, mixing until fully incorporated after each addition.

Pipe or spoon the dough onto the baking sheet in tree shapes and bake until golden.

Whip heavy cream until soft peaks form; fold in confectioners' sugar, additional whole milk, corn syrup, and green food coloring to create icing.

Assemble the cream puffs into a tree shape.

Decorate with icing, and top with the star-shaped sugar cookie.