• Start the dough in the evening for an overnight rise (10-12 hours at 68°F). Bake the next morning. If your room is warmer, the dough will rise faster.

Mix the Dough

• Combine flour, butter, sugar, and salt in a stand mixer (paddle attachment). Mix until the butter looks crumbly.
• Add starter and warm water. Mix until the flour is fully incorporated (finish with your hands if needed). Cover and let rest for 30 minutes.

Knead the Dough

• Switch to the dough hook and knead on medium-low for 6-8 minutes until soft and elastic. If sticky, add a dusting of flour.
• By Hand: Knead on a floured surface for 8-10 minutes until smooth and elastic.

Bulk Rise

• Cover the bowl and let rise overnight at room temperature (68°F) until doubled in size, about 10-12 hours.

Shape the Dough

• Grease an 8.5×4-inch loaf pan.
• Flatten the dough to release air bubbles, then roll into a log. Rest for 5-10 minutes. Tighten the shape by cupping the dough and place it in the pan, seam side down.

Second Rise

• Cover with lightly oiled plastic wrap and let rise until the dough is 1 inch above the rim of the pan, about 1 1/2-2 hours.

Bake the Dough

• Preheat oven to 375°F (or 500°F for better oven spring, reducing to 375°F when the loaf goes in).
• Bake on the center rack for 45-50 minutes, or until golden brown.

Cool and Store

• Cool in the pan for 10 minutes, then transfer to a rack to cool completely. Store in a plastic bag at room temperature for up to 3 days.