In a small bowl add the warm water and sugar, then sprinkle the yeast in and stir, set aside for about 10 minutes.

If using a stand mixer, attach the dough hook and add the flour baking powder, salt, and diced cold butter, mix on low speed until the texture resembles bread crumbs. (If using a large bowl, mix the flour, baking powder, and salt, then cut in the butter and mix, rubbing the butter throughout until it resembles crumbs).

Add the yeast mixture and buttermilk and bring together until a soft dough starts to form.

If using a stand mixer, continue to mix with the dough hook for about 3 - 5 minutes. then remove dough to a lightly flour-dusted surface, shape into a round loaf, cover with a clean towel and let rest for about 10 minutes. Proceed to #6 below.

If you're not using a stand mixture, on a lightly flour-dusted surface, turn out dough, dust lightly with more flour and knead gently until smooth. About 3 - 5 minutes. Let rest for about 10 minutes.

Punch down dough and shape into a round loaf, place on a parchment-lined or greased baking sheet or baking stone.

Cover with a clean towel and let rise in a warm place for about 30 minutes.

Preheat oven to 375F. Cut an "X" on top of the loaf, about 1/2 inch deep.

Place in oven and bake for 35 -45 minutes, until it's golden on top, and skewer or knife inserted comes out clean.