Step 1
Preheat oven to 350 degrees F (175 degrees C).
Step 2
Beat butter in a bowl using an electric mixer until fluffy about 2 minutes. Beat white sugar baking powder and salt into butter until just combined. Beat egg milk and vanilla extract into butter-sugar mixture; add flour and mix until dough is just combined. Cover bowl with plastic wrap and refrigerate until dough is slightly chilled about 10 minutes.
Step 3
Scoop dough into balls slightly larger than golf balls; flatten into cookies. Arrange cookies on a baking sheet.
Step 4
Bake in the preheated oven until edges are golden brown 10 to 20 minutes. Cool on baking sheet for about 5 minutes before transferring to a wire rack to cool completely at least 30 minutes.
Step 5
Butter a microwave-safe plate. Place marshmallows on the prepared plate.
Step 6
Microwave marshmallows until slightly puffed 10 to 15 seconds. Gently press marshmallows until bottoms slightly ooze.
Step 7
Whisk confectioners' sugar and water together in a bowl until icing is slightly thicker than drizzle-consistency. Pour icing over cookies so it runs over the edges reserving about 1 tablespoon.
Step 8
Melt chocolate chips in a microwave-safe glass or ceramic bowl about 30 seconds. Pour melted chocolate into a piping bag with a small tip or a plastic bag with a corner snipped.
Step 9
Press 1 marshmallow close to an edge of each cookie to be the snowman's head. Draw 'stick arms' onto the icing using the melted chocolate.
Step 9
Divide the reserved 1 tablespoon icing into 2 small bowls. Mix red food coloring into 1 of the bowls and orange food coloring into the other bowl. Decorate the snowmen with scarves or ties using the red icing and yellow icing.