Heat oven to 350 degrees. Line a baking sheet with parchment paper; set aside. In a large bowl, whisk together flour, sugar, salt, baking powder, and caraway seeds until well combined.
Using a pastry cutter or two knives in scissor fashion, cut in butter until the mixture feels like coarse meal. Stir in raisins until evenly distributed.
In a small bowl, whisk together buttermilk, egg, and baking soda until well combined. Pour buttermilk mixture into the flour-and-butter mixture all at once, and stir with a fork until all the liquid is absorbed and the mixture begins to hold together. It should resemble a rough biscuit dough. Using your hands, press the dough into a round, dome-shaped loaf about 8 inches in diameter. Lift the loaf from the bowl, and transfer it to the prepared baking sheet.
In a small bowl, mix the egg yolk and cream together. With a pastry brush, brush the egg wash over the loaf. With a sharp knife or razor, incise a cross, about 1/2 inch deep, into the top of the loaf. Transfer to the oven. Bake, rotating halfway through, until it is deep golden brown and a wooden skewer comes out clean when inserted into the center, about 70 minutes. Remove from oven, and transfer bread from the baking sheet to a wire rack to cool.