Preheat your oven to 450 degrees Fahrenheit. If you are using a cast iron skillet, preheat that as well.
Sift together the 2 cups of flour, heaping tablespoon of baking powder, and 1/4 teaspoon of baking soda together in a large mixing bowl.
Then add 1 teaspoon of salt and combine.
On a floured surface, use the dough scraper (or a knife) to cut the 6 tablespoons of cold butter into cubes. Use extra flour to keep the butter from sticking to the dough scraper.
With your hands, mix the butter into the flour mixture until it is mostly combined. Small pebbles of butter is fine.
Add 1 cup of kefir yogurt (or buttermilk) to the mixture and mix just until you have a dough you can work with. You can start with the spoon and then ditch the spoon and use your hands. If the dough is too sticky, add more flour. If it is too dry, add more yogurt.
Once the dough is combined enough to work with, place it on a floured surface. Be careful not to overwork the dough.
Flatten the dough out until it is about a half inch thick.
Use the biscuit cutter to make as many biscuits as you can. Do not spin the biscuit cutter.
Gather the remaining dough and flatten it out again to make more biscuits. Repeat this until the dough is all used up. You may have a small biscuit left in the end.
Place the biscuits on the pan or cast iron skillet so that they are touching the edge of the pan or skillet and each other.
Bake for 10 minutes or until they are golden brown.