Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.

In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, baking soda, and salt until well combined.

If using butter, add the cold, cubed unsalted butter to the dry ingredients. Use your fingertips or a pastry blender to cut the butter into the flour mixture until it resembles coarse crumbs.

Stir in the optional raisins and caraway seeds, if you are using them, ensuring they are evenly distributed.

Make a well in the center of the dry ingredients. Pour in the buttermilk.

Using a wooden spoon or your hands, gently mix until the flour is just moistened and a shaggy dough forms. Be careful not to overmix; a slightly lumpy dough is fine.

Lightly flour a clean work surface. Turn the dough out onto the floured surface and gently knead for about 1 minute, just enough to bring the dough together into a round, cohesive ball. Avoid excessive kneading, as this will develop the gluten and make the bread tough.

Transfer the dough ball to the prepared baking sheet. Using a sharp knife, score a deep 'X' into the top of the loaf, about 1/2 to 3/4 inch deep. This allows the heat to penetrate the center and helps the bread cook evenly.

Bake for 35-45 minutes, or until the crust is golden brown and the loaf sounds hollow when tapped on the bottom. If the top is browning too quickly, you can loosely tent it with foil during the last 10-15 minutes.

Remove the bread from the oven and transfer it to a wire rack to cool. For a softer crust, you can cover the bread with a clean tea towel while it cools.

Allow the bread to cool for at least 15-20 minutes before slicing and serving. It's best served warm with butter, jam, or alongside a hearty stew.