This makes two beautiful loaves. Courtesy of The New York Times Cooking Joan Nathan.

Ingredients:

1 ½ packages active dry yeast (1 1/2 tablespoons)

1 tablespoon plus 1/2 cup sugar

½ cup vegetable oil, more for greasing bowl

5 large eggs

1 tablespoon salt

8 to 8 ½ cups all-purpose flour

Poppy or sesame seeds for sprinkling

Directions:

• In a large bowl, dissolve yeast and 1 tablespoon sugar in 1 3/4 cups lukewarm water
• Whisk oil into yeast, then beat in 4 eggs, one at a time, with remaining sugar and salt. Gradually add flour. When dough holds together, it is ready for kneading. (You can also use a mixer with a dough hook for both mixing and kneading.)
• Turn dough onto a floured surface and knead until smooth. Clean out bowl and grease it, then return dough to bowl. Cover with plastic wrap and let rise in a warm place for 1 hour, until almost doubled in size. Dough may also rise in an oven that has been warmed to 150 degrees then turned off. Punch down dough, cover and let rise again in a warm place for another half-hour.
• To make a 6-braid challah,  take half the dough and form it into 6 balls. With your hands, roll each ball into a strand about 12 inches long and 1 1/2 inches wide. Place the 6 in a row, parallel to one another. Pinch the tops of the strands together. Move the outside right strand over 2 strands, then under 1, keep braiding with 1 strand over 2 and under 1 until completed. Tuck ends underneath.  Make a second loaf the same way. Place braided loaves on a greased cookie sheet with at least 2 inches in between.
• Beat remaining egg and brush it on loaves. Either freeze breads or let rise another hour.
• To bake, preheat oven to 375 degrees and brush loaves again. (If freezing, remove from freezer 5 hours before baking.) Then dip your index finger in the egg wash, then into poppy or sesame seeds and then onto a mound of bread. Continue until bread is decorated with seeds.
• Bake in middle of oven for 35 to 40 minutes, or until golden. Cool loaves on a rack. (I  baked for 30 minutes and it looked done, but one of the larger loaves was a little raw in the middle, so 32-33 minutes should be perfect). Any more than this I think they would be over baked. If you use a convection oven or convert your oven to convection, 35-40 minutes should work since the temperature would be lower and there would be a fan to cook more evenly.