Golden, crackling crust on the outside, tender and tangy crumb on the inside - classic Irish soda bread needs just four ingredients and zero yeast. Pair it with homemade Guinness butter (stout reduced with honey, whipped into salted butter) and you have the St. Patrick's Day side that steals the entire table.
Preheat your oven to 425°F. Line a baking sheet with parchment paper. This ensures the bread bakes up with a crisp bottom and doesn't stick.
In a large bowl, whisk together all-purpose flour, bread flour, baking soda, and fine salt. Cut the cold Irish butter into the dry ingredients using your fingertips or a pastry blender until the mixture resembles coarse crumbs. Keeping the butter cold helps create a tender, almost flaky crumb.
Pour in the buttermilk all at once and use a fork to quickly mix until the dough just comes together. Avoid over-mixing—this ensures a tender bread; overworking develops too much gluten, leading to a dense loaf.
Turn the dough onto a lightly floured surface. Gently shape into a round about 2 inches tall. Do not knead. Transfer to your prepared sheet and use a sharp knife to cut a deep cross on top—this helps heat penetrate to the center for even baking.
Bake for 35–40 minutes, until golden brown and the loaf sounds hollow when tapped on the underside. Cool on a rack at least 20 minutes before slicing to set the crumb.
While the bread cools, make the Guinness butter: In a small saucepan, combine Guinness and honey. Simmer over medium heat until reduced to 2–3 tablespoons, thick and syrupy (about 8–10 minutes). Cool completely.
Beat the softened Irish salted butter in a bowl. Slowly whip in the cooled Guinness reduction until fully incorporated and fluffy. The reduction adds pronounced stout flavor without excess bitterness or liquid.