In an electric stand mixing bowl combine yeast, 1 cup flour, 1 Teaspoon salt, 2 Tablespoons sugar and 1/2 Teaspoon baking soda .In a medium size metal sauce pan combine water, buttermilk and oil. heat to 120 degrees. Add the heated ingredients to the flour mixture. Beat 4 minutes on medium speed. Gradually add enough remaining flour until you have a soft dough. Knead with a bread hook until smooth. The dough will be soft and supple.Place the dough in an oiled bowl, turn to coat the dough, cover the bowl with a clean cloth. Place the bowl in a warm oven, turn the oven to the lowest temperature on the dial and let the oven heat up for 1 or two minutes then turn it off. Place the dough in the oven for 15 minutes to rise.After the dough has risen , press the dough into a greased 9 inch square baking pan. Lightly sprinkle flour over top of the dough, with a sharp knife cut the dough into 12 rolls, cutting almost to the bottom of the pan. Cover and let the dough rise in a warm place. The dough has risen enough when you touch the dough with your finger and the indentation from it remains. Bake in a preheated 400 degree oven for 15 - 20 minutes or until the roll tops are golden brown. Remove the rolls from the pan, serve.