1 cup luke warm
2 tablespoons sugar
2 teaspoons instant yeast
1 cup bread flour
Combine the ingredients for the sponge in the bowl of a stand mixer and cover with plastic wrap. Set aside and let rise for 1 hour.
2 large eggs
2 large egg yolks
2 tablespoons vegetable oil or butter, melted
3 cups bread flour
1 teaspoon salt
2 egg whites, beaten
Add the eggs and yolks to the sponge and stir until combined. Stir in the oil or butter, the flour and the salt until they come together in a ragged ball. Fit a stand mixer with a dough hook attachment and knead the dough until smooth, shiny and elastic – adding additional water or flour if necessary.
Remove the dough to a lightly floured surface and form into a ball. Place in a lightly oiled container, cover with plastic wrap, and let rise until doubled in volume.
Remove the dough again to a lightly floured surface. Cut into equal pieces (at least 3) and roll each piece into strands of equal length. Braid the strands into the challah loaf and place on a baking sheet lined with lightly oiled parchment paper. Cover with plastic wrap and set aside to proof approximately 1 hour.
Preheat the oven to 350E with the
rack on the middle shelf. When the dough has increased in volume by 1½
times, brush the entire loaf with the beaten egg whites. Place the dough in
the oven and bake until golden brown and just hollow-sounding when tapped
(approximately 40 to 45 minutes. Remove the bread to a wire rack, cool, cut