Preheat oven to 450°.

The butter must be really cold to make the biscuit dough rise properly. Cut butter into small pieces and place back in the refrigerator until ready to incorporate into the dough.

Combine the dry ingredients in a large bowl. Using a pastry cutter, cut cold butter into flour mixture (you can also use a food processor and pulse lightly). *Don’t over-do it: You are looking for pea-size pieces of butter throughout the dough. Add milk and egg, and mix just until the ingredients are combined (dough will be sticky, don’t keep working it. You should be able to see the butter pieces in the dough).

Turn the dough out onto a floured surface. Sprinkle flour onto top of the dough so it won’t stick to your fingers, knead lightly (if the dough is super sticky, sprinkle some additional flour). Gently roll the dough out to ¾- to 1-inch thickness; cut with a biscuit cutter or anything round. Place biscuits on a lightly greased baking sheet or parchment-lined baking sheet. Brush the tops of the biscuits with heavy cream; sprinkle coarse sugar crystals all over the top. Bake for 10 to 15 minutes or until golden brown on top.