*This amount of cayenne produces a biscuit that is noticeably hot, but not searingly so; adjust the quantity to your own taste.
In a large bowl, mix together the flour, cayenne, mustard, baking powder and salt. Cut in the butter and shortening, then add the cheese. Stir in the milk and currants to form a stiff, cohesive dough. Cover the bowl with plastic wrap, and refrigerate the
Transfer the dough to a well-floured work surface, and roll it out about 1/4-inch thick; this is just about as thin as the currants allow you to roll it. Using a rolling pizza wheel (the easiest method), a sharp knife or a baker's bench knife, cut the dou
Bake the biscuits in a preheated 375°F oven for 14 to 15 minutes, or until they're a light golden brown, and a slightly darker brown around the edges. Watch out?they start to brown very quickly towards the end of the baking time, so keep your eye on them.