Preheat oven to 450 degrees.
Combine flour, orange zest and 2 Tablespoons sugar in food processor. Cut butter into 4-5 pieces and add to flour mixture. Pulse until butter is in pea-sized pieces.
Place processed flour mixture into a glass bowl. Add half and half and juice from orange and mix well.
Place dough on lightly floured surface and pat into rectangle that is one inch thick
Lightly moisted top of dough with water. Sprinkle remaining tablespoon of sugar over top.
Bake 10-12 minutes until golden brown. Allow to cool.
To make glaze, combine orange juice with powdered sugar and mix until smooth. Drizzle over scones.