Activate the Yeast: Combine the warm water, yeast, and 1 tablespoon of the date syrup in a large bowl. Let it sit for 5 to 10 minutes until it becomes frothy.
Mix the Wet Ingredients: Whisk in the oil, 1 large egg, the salt, and the remaining date syrup until smooth.
Form the Dough: Gradually add 4 cups of flour, stirring until a cohesive dough forms. Turn it out onto a floured surface and knead for 8 to 10 minutes, adding the remaining ½ cup of flour a little at a time if the dough is too sticky, until smooth and elastic.
First Rise: Place the dough in an oiled bowl, cover it with a damp towel or plastic wrap, and let it rise in a warm place for 1 to 2 hours, or until doubled in size.
Shape and Braid: Punch down the dough and divide it into 3 or 4 equal pieces. Roll each piece into a long strand, then braid them together. Transfer the braided loaf to a parchment-lined baking sheet.
Second Rise: Cover the shaped loaf and let it rise again for 30 to 45 minutes until puffy.
Bake: Preheat your oven to 350°F (175°C). Beat your remaining egg and brush it generously over the risen challah for a glossy crust; sprinkle with sesame seeds if desired. Bake for 25 to 30 minutes, or until golden brown and hollow-sounding when tapped on the bottom.
