In a large bowl, mix together flour, salt, and baking soda.
Add buttermilk, a cup at the time and mix either with your hand or wooden spoon until incorporated. Dust the dough with more flour, knead for few seconds until you form a ball, cross cut on top. The dough needs to be soft and sticky.
Oil the pan and transfer the dough to the baking pan. At this point, if you are going to add oats on top, brush with a little oil and add oats.
Bake for 40-45 minutes, depending on the size and your oven. If you like the crust crunchy leave it in the oven for up to 50 minutes. The bottom of the bread should sound almost hollow when you tap on it.
Recipe Notes
You can add other grains/seeds in the flour. I love adding flax seeds, sunflower seeds as well as pumpkin seeds. Remember, this bread supposes to look rustic.