Ingredients

1 3/4 cups all-purpose flour 

1 3/4 cups bread flour 

2 teaspoons coarse salt 

1/4 cup warm water 

1/3 cup sugar 

1 package (2 1/4 teaspoons) active dry yeast 

6 large eggs, room temperature 

1 teaspoon finely grated lemon zest 

1 1/2 sticks unsalted butter, room temperature, cut into 6 pieces, plus more for plastic wrap 

Preparation

Whisk together both flours and salt. In the bowl of a mixer, combine warm water, sugar, and yeast. Let stand until foamy, 5 minutes.

Add eggs, zest, and flour mixture to yeast mixture. Beat on medium-high speed with a dough hook until dough pulls away from sides of bowl, about 5 minutes.

Beat in butter, one piece at a time; continue beating until fully combined and dough is silky but still sticky, about 5 minutes more. Cover with buttered plastic wrap; let rise in a warm spot until doubled in bulk, about 1 hour.

Chill 1 hour. Punch down dough. Refrigerate, covered, 1 hour or overnight.