Prep the Oven and Vessel: Preheat your oven to 375°F. Generously grease a casserole dish or a cast iron pot with butter.
Whisk Dry Ingredients: In a large mixing bowl, whisk together the flour, baking soda, salt, and sugar. If using raisins, stir them in now to ensure they are well-coated in flour.
Measure the Liquid: Crack the two eggs into a 2-cup measuring cup and whisk them lightly. Add enough buttermilk to the eggs until the total liquid reaches the 1-cup mark.
Mix the Dough: Pour the egg and buttermilk mixture into the dry ingredients. Mix until combined. The dough should be sticky; if it feels too dry, add a splash more buttermilk. If it’s overly wet, add a tablespoon of flour.
Shape and Score: Scrape the sticky dough into your prepared baking vessel. Use a spatula or floured hands to pat the top smooth. Use a sharp knife to cut a deep cross into the top of the dough.
Bake: Place in the center of the oven and bake for 45 to 55 minutes.
The Skewer Test: At the 45-minute mark, insert a skewer into the center. If it comes out clean, it’s done. Tip: If the top is browning too quickly before the center is set, tent the vessel loosely with aluminum foil.
Rest and Serve: Remove from the oven and let the bread sit uncovered in the pot for 15 minutes. This allows the crumb to set. Slice and serve warm with plenty of butter and jam.