Preheat the oven to 450°.

In a large bowl, mix together the flour, salt, sugar, baking powder, and cream of tartar.

Cut in the shortening until the mixture resembles coarse crumbles.

Make a well in the center and add the milk all at once; stir with a fork until the dough leaves the sides of the bowl.

Turn out the dough onto a lightly floured surface and knead about 5 times.

Roll or pat the dough to ½-inch thickness and then cut with a biscuit cutter.

Place the biscuits on an ungreased baking sheet and bake for 15 minutes or until done.