Dissolve yeast in warm milk and let it sit for 5–10 minutes.

In a large mixing bowl, combine flour, sugar, and salt.

Add melted butter, eggs, lemon zest, and vanilla to the flour mixture.

Pour in the yeast mixture and mix until a dough forms.

Knead the dough on a floured surface for about 8–10 minutes until smooth.

Place the dough in a greased bowl, cover, and let it rise for 1–2 hours or until doubled in size.

Punch down the dough and divide it into three equal pieces.

Roll each piece into a long strand, then braid them together.

Place the braided dough on a baking sheet, cover, and let it rise for another 30 minutes.

Preheat the oven to 350°F (175°C), brush the dough with the egg wash, and sprinkle with sugar if desired. Bake for 25–30 minutes until golden.