Preheat the oven to 350°F. Grease a 9-inch round cake pan.
In a large bowl, mix together the flour, baking soda, and salt. Cut in the butter until the mixture resembles coarse crumbs.
Stir in the buttermilk until the dough comes together. Knead the dough on a lightly floured surface for 2 minutes. Form the dough into a round loaf and place it in the prepared cake pan.
Bake for 35 to 40 minutes, or until golden brown and a toothpick inserted in the center comes out clean.
Let the bread cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
Interesting Facts
Irish soda bread is traditionally served with butter and jam.
The bread gets its name from the baking soda used to help it rise.