Ingredients

2 active dry yeast 

2 cups warm milk 

9 cups all-purpose flour, plus more for dusting 

1 1/2 cups sugar 

2 teaspoons mahlepi 

1/2 cup simmering water, plus 1 Tablespoon water 

8 tablespoons (1 stick) unsalted butter, melted and cooled, plus more for bowl and baking sheet 

6 large eggs 

1 tablespoon grated orange zest 

1 tablespoon grated lemon zest 

1/2 teaspoon coarse salt 

4 hard-boiled eggs, dyed red 

1 tablespoon sesame seeds 

Preparation

In a large bowl, dissolve yeast in warm milk. Stir in 1 cup flour and 1/2 cup sugar. Cover bowl with plastic wrap, and set aside for 1 hour. Meanwhile, steep mahlepi in 1/2 cup simmering water. Let stand for 5 minutes. Strain, and discard mahlepi. Let cool.

Add mahlepi infusion, butter, and 5 eggs to yeast mixture; combine thoroughly. Add orange and lemon zests. Sift in remaining 8 cups flour, remaining 1 cup sugar, and salt; stir with a wooden spoon until dough forms. Knead dough in bowl until smooth, about 10 minutes. Form dough into a ball, and transfer to a lightly buttered bowl. Cover, and let rise for 2 hours.

Punch dough down, and transfer to a lightly floured surface. Divide dough into six equal pieces. Roll each piece of dough into a rope, about 15 inches long. Tightly braid 3 ropes together, beginning in the middle. Repeat with remaining 3 ropes. Tuck a red-dyed egg into the first and last plaits, using a small piece of coiled dough to hold each egg in place if necessary. Place each loaf on a buttered baking sheet, cover loosely with plastic wrap, and set aside to rise for 1 hour.

Preheat oven to 350 degrees. Beat remaining egg with 1 tablespoon water. Brush bread with egg wash, and sprinkle with sesame seeds. Transfer to oven, and bake until golden, 50 to 60 minutes.