From the matzah of Passover to the challah of Shabbat, much of our Jewish tradition focuses on grain. Between Passover and Shavuot, when we count the Omer — the days between the ancient barley and wheat harvests — I like to think about the importance of wheat, to our ancestors as well as to us today.

The wheat our ancestors grew was difficult to cultivate, and processing was arduous. By the Bronze Age, it was replaced by emmer, a type of farro, and in Roman times by triticum aestivum, today know as common wheat and the basis for modern wheat bread. It was in medieval Europe where Jews began marking Shabbat with challah.

I am always playing with my challah recipes, and this version, stuffed with sweet, sautéed onions and topped with my “everything” seasoning, is a tasty way to honor the importance of wheat in the Jewish tradition.

Onion-Stuffed Challah with Everything Topping

Makes 1 loaf

For the dough:

• 1 package or 2¼ tsp. active dry yeast (not rapid-rise)
• ½ cup warm water (about 100-110 degrees)
• 1 tsp. plus 2 Tbs. sugar
• 3 eggs
• 1 Tbs. plus ¼ cup water
• 2 Tbs. oil
• 1½ tsp. salt
• 3-4 cups bread flour

For the filling:

• 3 Tbs. oil
• 3 cups chopped sweet yellow onion (such as Maui)
• 1½ tsp. poppy seeds
• ½ tsp. salt
• ½ tsp. garlic powder
• ½ tsp. ground black pepper

For the topping:

• 2 Tbs. homemade or commercial Everything Bagel topping (see below)

Dissolve yeast in warm water with 1 tsp. sugar. Let stand until bubbly. Separate yolk and white of 1 egg. Place yolk in small bowl. Mix with 1 Tbs. water. Cover and set aside. Mix white and remaining eggs in large bowl. (Set aside 1 Tbs. for brushing dough.) Mix in oil, remaining sugar, salt and ¼ cup water. Add yeast mixture. Gradually add 3 cups flour. Mix well until dough is smooth and not sticky, adding more flour if needed. Turn out onto a lightly floured board. Knead for 12-15 minutes, adding more flour if dough becomes sticky. Place dough in a greased bowl. Turn to coat. Cover. Let rise 45 minutes until doubled in bulk.

While dough is rising, make filling. Heat oil in large skillet over medium heat. Sautéé onions until very soft and medium brown, stirring often. Stir in poppy seeds, salt, garlic powder and pepper. Sauté 1 minute. Scrape into bowl. Let cool.

Heat oven to 350 degrees. Cover baking sheet with foil. Punch down dough and knead for a few minutes. Divide dough into thirds. Form 3 ropes, each about 12-13 inches long. Take one rope and place on lightly floured board and flatten with a floured rolling pin until about 3-4 inches wide. Leaving a ½-inch margin at top and bottom, place third of filling in a thin line in the center of the flattened rope. Roll rope closed, pinching and folding as necessary. No filling should be visible. Roll rope on board until smooth. Place seam side down on foil-covered sheet. Repeat with other ropes. Braid challah. Brush with beaten egg. Sprinkle with topping. Bake about 35-40 minutes until golden brown, the bottom sounds hollow when tapped and/or an instant-read thermometer reads 200 degrees. Cool on rack.

Everything Topping: Combine 1 Tbs. each sesame seeds, black sesame seeds, poppy seeds, dried grated or minced garlic (not powdered), dried grated or minced onion (not powdered) and kosher salt or coarse sea salt. Adjust quantities to taste. (Optional: Add 1 Tbs. caraway seeds.) If black sesame seeds are not available, use 2 Tbs. regular ones. Store extra topping airtight.