In large bowl, place flour and sliced cold butter. Cut butter into flour with a fork or pastry cutter until fully incorporated and it resembles lumpy flour. Place this bowl in the refrigerator for ten minutes.
After ten minutes have passed, stir sugar and chocolate chips into flour mixture until well blended. Add milk and stir just until moistened (can add 1/4 cup more milk if need be).
Turn dough out onto lightly floured surface. Dip palms of hands in flour and pat out into a rectangular shape. Gently fold the right side over onto the middle of the rectangle. Fold left side over on top of folded right side - like you are folding a piece of paper to put into an envelope.
Pat this out again into a rectangle and repeat folding process once more.
Dip juice glass or biscuit cutter into flour and cut out biscuits. Place biscuits on lightly greased pans with their sides touching. Bake at 450 for 14-16 minutes, or until lightly golden on top.
To make glaze
Stir together confectioner's sugar, vanilla, and milk until smooth. Brush over top of biscuits. Allow to sit for a few minutes before serving.