Preheat oven to 350 degrees.
Beat butter and sugars in a large bowl until creamed. Mix in eggs. Mix in vanilla and milk.
Add dry ingredients and mix until cookie dough forms. Scrape sides of the bowl, making sure all dry ingredients have been mixed in.
Scoop dough (using a medium cookie scoop) or roll into cookie dough balls ad place onto parchment paper-lined cookie sheets. Bake for 10 minutes. While cookies bake cut marshmallows in half with scissors.
Place a marshmallow half (sticky side down) onto each hot cookie. Place cookies back in the oven and bake an additional 2-3 minutes (marshmallows should be slightly puffed). DO NOT OVERBAKE MARSHMALLOWS.
Press each marshmallow down with the back of a spoon.
Cool cookies completely on cookie sheets.
Microwave glaze ingredients in a microwave-safe bowl for 1 minute (30-second increments). Stir. Microwave in 10-20 second increments, stirring in between, until smooth and creamy.
Dip tops of cookies into the chocolate glaze OR spoon chocolate glaze over each cookie. Use a little or a lot, depending on preference.
Allow glazed cookies to cool 5-10 minutes then sprinkle with crushed graham crackers (optional).