The perfect accompaniment to a good hamburger is a good bun: soft and flavorful, with enough body to stand up to condiments. These sourdough buns are fast and easy to make.
Stir together sourdough starter, butter, milk, egg, and salt. Don’t worry if there are still some chunks of butter in the mixture.
Add the flour, 1/2 cup at a time, mixing with a spoon until it comes together enough to turn out onto a bread board or clean countertop.
Knead the dough until it is smooth and satiny, about 10-20 minutes.
(Optional) Refrigerate the dough for up to 24 hours to get a more flavorful bun. Bring it back to room temperature before continuing.
Let the dough rest at room temperature 15-20 minutes, then roll it out 1/2 inch thick.
Use a 3- or 4-inch biscuit cutter to cut bun shapes and transfer them to an ungreased baking sheet. Re-roll the dough and cut more shapes until all the dough has been used.
(Optional) Press a light layer of sesame seeds gently into the buns.
Cover the buns lightly and let rise until doubled in bulk – between 1 and 4 hours.
Preheat the oven to 350°F. Bake buns 18-20 minutes.
Cool on the baking sheet for 5 minutes, then transfer to a wire rack to continue cooling. Cool completely before slicing in half horizontally.
