Preheat the oven to 350 degrees Fahrenheit. Line a rimmed baking sheet with parchment paper.
In a large bowl, whisk together the flour, sugar, salt, baking powder, and baking soda.
4 cups all purpose flour, 3 tablespoons granulated sugar, 1 1/2 teaspoons table salt, 1 teaspoon baking powder, 1 teaspoon baking soda
In a large measuring cup, mix together the buttermilk and melted butter. Then pour into the flour mixture. Using a spatula, fold the buttermilk and butter mixture into the flour until it starts to combine. Then fold in the raisins if using. The dough will still be loose when you head to the next step.
1 3/4 cups buttermilk, 2 tablespoons unsalted butter, 1 cup raisins
Turn the dough out onto a well-floured surface and gently knead a few times until the dough comes together. Then shape it into a ball. Flatten slightly, about a 7-inch round, and put it on the prepared pan. Using a serrated knife, cut an X about 1/4 inch deep into the loaf.
Bake for 45 to 55 minutes, rotating once during baking, until the loaf is golden brown and a toothpick inserted in the middle comes out clean. I like to cover my loaf with aluminum foil halfway through baking so that the top doesn't over-brown.
Brush the loaf with melted butter and transfer to a wire cooling rack. Allow it to cool for an hour before slicing with a serrated knife. 1 tablespoon unsalted butter