Combine the butter, vanilla extract, and powdered sugar in a large mixing bowl. Beat with an electric mixer until smooth and creamy.

Add the flour, salt, and baking powder. Pour in the milk one tablespoon at a time and mix until a dough forms.

Chill the dough in the refrigerator for at least 1 hour or up to overnight.

Preheat the oven to 350°F and line your baking sheet with parchment paper.

Roll out the chilled dough to about 1/4 inch thick. Use a large round cookie cutter to cut out the shapes.

Bake the cookies for 9 to 10 minutes.

Let the sugar cookies cool completely before decorating.

In a bowl, combine the powdered sugar, meringue powder, and vanilla extract. Beat for 2 to 3 minutes while adding water gradually, one teaspoon at a time, until stiff peaks form.

Divide the icing into two bowls. Keep a little more than half of it white, then add brown liquid food color to the remaining icing.

Dip one side of each cookie into the white icing and let it dry.

Pipe the antlers and eyes on each cookie using the brown decorating icing.

Add a small dot of brown icing to mark the nose, then press a green M&M onto the spot to finish the reindeer face. Repeat with the remaining cookies, and you're done.