Preheat your oven to 220°c (200°c for fan-assisted oven, Gas Mark 7 or 425°F). Grease two baking sheets with a little excess margarine/butter and set aside.
Sift the flour, salt, baking powder, and cayenne pepper into a large bowl, holding the sift up to allow some air into them. Gently stir in the sugar.
Using the tips of your fingers, rub the margarine/butter into the dry ingredients, again, lifting as you do to allow air in. Continue until you have a sandy consistency.
Keep aside a small amount of the cheese (for topping your scones) and stir through the rest of cheese, before creating a well in the centre of your ingredients.
Whisk the milk and crème fraiche together before pouring into the well. Using your hands, gently bring the ingredients together to form a soft, slightly sticky dough.
Turn out onto a floured work surface and gently knead together, before stretching the dough to about 1cm thickness. Fold the dough over itself (like a book) so you have two layers, and gently press together until your dough is about 2cm thick.
Using a cookie cutter of your choice, cut your scones out and place them onto your pre-greased baking sheets. The smaller your cutter the more scones you will get. Reform and stretch the dough as required to use all of the dough.
Leave your scones to rest on the tray for about 10 minutes before brushing the tops with some extra milk and topping with the leftover cheese.
Bake in your preheated oven for 10 minutes. If you are making smaller scones, keep a close eye on them as you may need to reduce the baking time to suit.
Once cool enough to touch, transfer to a wire rack to cool completely or enjoy whilst still warm.