Place a sheet of parchment paper on a baking sheet, or lightly spray with non-stick baking spray.
Add flour, salt and baking soda to a large bowl and using a fork mix well.
Add 1-¼ cup of buttermilk and mix until the flour is moistened and partially comes together. If necessary, add a little more buttermilk if your dough is too dry.
Pour this mixture out onto a lightly floured surface and gently knead a few times until the dough forms a nice ball and holds together. Do not knead too much, or your bread will be tough.
Shape the dough into approximately a 6-inch disk about 2 inches high and place it on your baking sheet.
Using a sharp knife, cut an X about 1 inch deep and extend it almost to the edges of the dough. This helps it cook in the middle.
Bake for about 35 minutes or until the bread is golden brown and sounds hollow when you tap on it.
Transfer to a rack to cool. Serve warm with butter.
Leftovers, if you have any, should be stored in an airtight container. Because there are no preservatives, it will only last about three days on your counter. However, you can freeze it for two to three months. If you do have leftovers, they are delicious sliced, toasted, and topped with butter and or jam.Be sure to use a "dry" measuring cup to measure the flour, and a "liquid" measuring cup when measuring the buttermilk. Liquid measuring cups usually are glass or plastic and have a handle that allows you to pour the liquid. Use the "spoon and level" method to measure your flour. Use a spoon to fluff up the flour, then fill your dry measuring cup with flour using the spoon and level it off with the flat blade of a knife. When kneading your dough, less is best. It's not supposed to look perfect, a few bumps here and there are fine. Don't skip the step of cutting the cross in the dough. It helps the insides cook all the way through.