Beat butter and sugars in a large bowl with electric mixer on medium speed until light and fluffy. Add milk and vanilla. Stir in flour, baking soda and salt and mix on low speed (or by hand) until incorporated. Stir in chocolate chips. Cover and chill dough for about 30 minutes.
When dough is firm enough to handle, form dough into 1-inch balls and arrange on a baking sheet lined with waxed paper. Place sheets in freezer & let chill for 30 minutes.
Melt baking chocolate in a double boiler or microwave according to package directions. Using a fork or a toothpick, dip the cookie balls into the melted chocolate, covering completely with the chocolate. Tap fork on the side of the bowl to remove any excess coating, and return ball to waxed paper (slide off the fork using the toothpick). Let the cookie balls harden at room temperature or in the fridge.
Decorate with colored chocolate by putting other types of melted chocolate in a zipper top bag & cutting the corner to the size of "drizzle" you'd like. Enjoy!
NOTE: If you are concerned about eating raw flour, you can quickly "bake" the flour before using it by spreading it on a cookie sheet and toasting it in the oven for 10-15 minutes at 350. Be careful not to let it burn.