Prepare 2 baking sheets with parchment or a silpat for easier cleanup.Preheat the oven to 425 degrees F.
In a large bowl, stir together the flour, sugar, baking powder and salt. Cut the butter in using a pastry cutter or your hands, till it resembles coarse crumbs. You should see pea-sized chunks of butter.
In a smaller bowl, whisk the egg and buttermilk. Make a well in the center of the dry ingredients, pour in the liquids and stir with a wooden spoon till the dough has pulled in most of the dry ingredients. Stir in the Gruyère, bacon and rosemary before the dough has completely come together.
Scoop the dough and drop the by the spoonful onto the prepared baking sheets and, if you like, whisk an egg with a few teaspoons of water and brush over the top for a shinier appearance.
Bake for about 15 minutes, moving sheets from top to bottom and front to back halfway through baking. Cool briefly and serve warm. Makes 18 scones. Recipe by Mani Niall.
Watch the video on how to make these scones on our YouTube channel!