Preheat oven to 450°F. Move a rack to the top of the oven.

In a bowl combine the baking soda and cream of tartar and mix thoroughly.

Add flour and salt and mix thoroughly.

Slice the butter into 1/16-inch thin squares and distribute over the top of the flour.

Work quickly, pressing each butter slice between your thumb and fingers to press into the flour and make the pieces even thinner. They will break apart. You want to end up with flakes of butter/flour mixture of different sizes.

Pour the buttermilk over the top, and stir quickly until the dough just comes together, about 8 to 10 stirs.

Turn the dough out onto a floured work surface, and gently knead about 10 times. Kneading biscuits is more like fold-and-press, fold-and-press.

Press or roll dough to a thickness of 1/2-inch and cut out biscuits.

Place the biscuits on a baking sheet and bake on the top rack for 10-14 minutes or until lightly browned.