In an oversized mixing bowl, start by dissolving the yeast and sugar in 2 cups of warm water. Allow it to sit for roughly 15 to 20 minutes until it becomes thick and frothy.
Next, introduce the eggs, honey, oil, salt, the remaining three cups of water, and half of the flour into the bowl. Stir until a loose batter forms. Gradually add the rest of the flour in batches, a couple of cups at a time. Be cautious toward the end, as you might not require all 18 cups of flour. Conversely, you might need a bit more. The dough should attain a soft texture without being overly sticky. Once the dough has absorbed enough flour, knead it for a couple of minutes directly in the bowl. (You can opt for either manual kneading or use a mixer for this recipe.)
Cover the dough with a damp towel or plastic wrap and place it in a warm spot for approximately 1½ hours to allow it to rise. The dough should double in size during this time.
After the dough has risen, gently punch it down and let it rest for 10 minutes. Then, divide it into 6 equal portions.
Following the provided pictures and instructions, braid the dough. Position the resulting braided loaves on lightly greased pans and let them rise for an additional 40 minutes.
Prepare an egg mixture by beating an egg with honey and vanilla. Carefully brush this mixture over the loaves.
Bake the loaves at 375°F for about 45 minutes until they turn golden on top and have a firm bottom.
Let your loaves cool before serving and you’ll have some delicious Challah to share!