Preheat the oven to 350˚F. Line a loaf pan with parchment paper and set aside.
In a medium bowl, mix together the flour, salt, and baking soda and set aside.
In a separate bowl, cream together the butter and the stevia until fully combined. Add in the eggs one at a time, mixing after each addition. Mix in the vanilla extract and sour cream until fully incorporated.
Slowly mix in the dry ingredients into the wet ingredients until just combined.
Pour the batter into the prepared loaf pan and bake in the preheated oven for 60-65 minutes, or until a toothpick inserted comes out clean.
Remove from the oven and allow to cool in the pan on a wire rack for around 10 minutes. Remove from the pan and allow to cool on the wire rack completely.