1. Arrange oven rack in center of oven. Heat oven to 325 degrees F. Line a large cookie sheet with parchment paper.
2. With a whisk, combine 2-3/4 cups of the flour, the granulated sugar, baking powder, baking soda, and salt in a large bowl; stir in raisins and caraway seeds. Whisk together eggs and buttermilk in another bowl. Stir buttermilk-egg mixture into dry ingredients with a wooden spoon just until blended (dough will be very sticky, but that's okay).
3. Sprinkle the remaining 1/4 cup flour onto a work surface. With lightly floured hands, turn and gently knead dough to incorporate most of the flour. Shape dough into a 6-inch round; transfer to center of prepared cookie sheet (dough will be soft and slightly sticky). With a sharp paring knife, make a 1/2-inch-deep X across the top of the loaf.
4. Bake loaf until a toothpick inserted in center comes out clean, about 1 hour. Transfer loaf with a large spatula to wire rack and cool completely. Slice with a serrated knife and serve with butter and jam, if desired. Makes twenty 1/2-inch slices.