Prepare the starter: Mix the starter ingredients in a bowl, cover, and let sit for 1 hour until bubbly and airy.

Prepare the dough: Melt butter and set aside to cool. In a separate bowl, mix 1 cup flour with sugar, dry milk, salt, and mahlep.

Stir eggs into the risen starter, then mix in cooled melted butter and orange zest.

Gradually add the flour mixture and remaining flour until a soft dough forms. Knead until smooth and elastic.

Cover the dough and refrigerate overnight (8–12 hours).

The next day, remove the dough and knead gently to deflate.

Divide into three pieces, roll into 16-inch strands, and braid. If using eggs, tuck them into the braid at intervals.

Place the braid on a parchment-lined baking sheet, cover, and let rise for 2–2.5 hours.

Preheat oven to 350°F (175°C). Brush with beaten egg wash.

Bake for 20 minutes, then gently press the eggs further into the braid. Continue baking for 40–50 minutes until golden brown (internal temp: 190°F).

If desired, brush with warm honey glaze. Cool completely before serving.