Lightly grease a 14" dutch oven or line with parchment paper.
Preheat to 500 degrees. This is a hot oven so use lots of coals on the bottom and the top to preheat. Be sure to remove most of the bottom coals just before you begin to bake the biscuits or you'll burn the bottoms.
In a mixing bowl, sift together the dry ingredients.
Cut in the shortening with a pastry blender, or two knives. Your done when there are little balls of dough about the size of a pea.
Pour in all of the milk at once. Stir with a fork until just mixed. Too much mixing will release the gluten and make a heavy biscuit. The dough will be quite wet but able to retain its shape.
Use a soup spoon and drop the biscuits into the dutch oven. Give each biscuit a little room to grow.
Place the lid on loaded heavy with hot coals. Place the oven back on a bed of just a very few coals. Bake for 8 to 10 minutes, or until golden brown.
Remove and serve immediately with lots of butter and sweet jam.