In a large mixing bowl (or stand mixer bowl), combine warm water (105-115°F / 40-46°C), 1 tablespoon of the granulated sugar, and active dry yeast. Stir gently and let sit for 5-10 minutes until foamy. This indicates the yeast is active.

To the foamy yeast mixture, add the remaining granulated sugar, 2 large eggs + 1 egg yolk (reserving 1 large egg for egg wash later), vegetable oil, and honey. Whisk until well combined.

Gradually add 3 cups of all-purpose flour and the salt to the wet ingredients. Mix on low speed with a dough hook (or with a wooden spoon) until just combined.

Continue adding the remaining flour, 1/2 cup at a time, until a shaggy dough forms and pulls away from the sides of the bowl. The dough should be soft and slightly sticky, but not overly wet. Knead with the dough hook for 8-10 minutes on medium-low speed, or by hand on a lightly floured surface for 10-15 minutes, until the dough is smooth, elastic, and passes the windowpane test (you can stretch a small piece thin enough to see light through it without tearing).

Lightly grease a clean large bowl with a little oil. Transfer the dough to the bowl, turning it once to coat. Cover the bowl tightly with plastic wrap or a clean kitchen towel. Let the dough rise in a warm, draft-free place for 1.5 to 2 hours, or until doubled in size.

Gently punch down the risen dough to release air. Transfer it to a lightly floured surface. Divide the dough into two equal portions for two loaves. For each loaf, decide on your preferred braid (e.g., 3-strand, 4-strand, or 6-strand).

For a 6-strand braid (recommended for classic Challah look): Divide one portion of dough into 6 equal pieces. Roll each piece into a long, even rope, about 16-18 inches long. Pinch the tops of the six ropes together firmly. Arrange the ropes in a specific pattern (e.g., three on the left, three on the right). Follow a braiding technique (e.g., from right to left: 6 over 3, 2 over 5, 4 over 1, then repeat). Pinch the ends firmly to seal.

For a 3-strand braid: Divide one portion of dough into 3 equal pieces. Roll each piece into a long rope. Braid them like a regular hair braid. Pinch the ends firmly to seal.

Carefully transfer each braided loaf to a baking sheet lined with parchment paper. Cover loosely with a clean kitchen towel or plastic wrap. Let rise in a warm place for another 45-60 minutes, or until visibly puffy.

About 20 minutes before baking, preheat your oven to 350°F (175°C). In a small bowl, whisk the remaining large egg with 1 tablespoon of water until well combined. This is your egg wash.

Gently brush the risen challah loaves generously with the egg wash. If desired, sprinkle with sesame or poppy seeds.

Bake for 30-35 minutes, or until the challah is deep golden brown and sounds hollow when tapped on the bottom. If the challah is browning too quickly, you can loosely tent it with aluminum foil for the last 10-15 minutes.

Transfer the baked challah loaves to a wire rack to cool completely before slicing and serving.