Certain and various biscuits

Biscuits—what Uncle John's Original Bread Book says
1 Tb baking powder
1/2 tsp salt
2 c normal flour
4 Tb butter
1 c milk

Biscuits—what the bag of self-rising flour we happened to have says
1/2 tsp baking soda
2.5 c self-rising flour
2 tsp sugar
1/2 c butter
3/4–1 c buttermilk

Biscuits—a good variation/combination of the two
1 Tb baking powder
1/2 tsp salt
2 c normal flour
2 c self-rising flour
1 stick butter
1 c plain yogurt
1 c milk

In all cases: mix dry ingredients, cut in cold butter, stir in
milk-like substance, knead gently and fold over a few times, cut into
biscuits, bake on ungreased sheet at 450F for 10–15 min, serve warm to
your friends.