Preheat oven to 400
Combine flour, baking powder, salt and sugar in bowl of mixer using paddle attachment.
Add butter and mix on low until butter is combined and crumbly.
With mixer still on low, add half-and-half and mix until combined.
Turn out dough on to floured surface and knead a few times.
Roll out dough to about 3/4" thick. Fold dough over once and roll out again. fold and roll a second time.
Using a biscuit cutter (or water glass) cut out biscuits and place on baking sheet lined with parchment.
Make egg wash (one egg + 1 tbsp water) and brush over top of biscuits.
Bake for about 18 minutes (start checking at 15 minutes) until tops are golden brown.
