Matzoh Vegetable Stuffing

Ingredients

• 2 slices celery stalks 
• 0.8 pound crimini mushrooms trimmed sliced for shitakes (removed )
• 8  eggs plain unsalted
• 4 large eggs lightly beaten
• 2 medium fennel bulb cored trimmed coarsely chopped ()
• 0.5 cup flat parsley finely chopped
• 5 tablespoons olive oil divided plus more for greasing dish
• 1 pound onion chopped ( 2 cups)

Equipment

• bowl
• frying pan
• oven
• baking pan
• aluminum foil
• colander

Directions

1. Preheat oven to 400°F with rack in middle.
2. Heat 3 tablespoons oil in a large heavy skillet over medium-high heat until oil shimmers. Sauté mushrooms with 1/2 teaspoon kosher salt and 1/4 teaspoon pepper until the liquid they give off has evaporated and mushrooms are browned, about 10 minutes.
3. Transfer to a large bowl.
4. Add remaining oil to skillet, reduce heat to medium, and cook onion, fennel, and celery with 1/2 teaspoon salt and 1/4 teaspoon pepper until softened and golden, about 15 minutes.
5. Transfer to bowl with mushrooms.
6. Grease baking dish with olive oil. Spoon mixture evenly into dish, cover with foil and bake until set, 25 to 30 minutes. For a top with some crisp and browned edges, uncover and continue to bake about 5 minutes more.
7. Rinse Matzoh in a colander under hot running water until just softened, 15 to 30 seconds.
8. Drain well.
9. Add to vegetables with eggs, parsley, 3/4 teaspoon salt, 1/2 teaspoon pepper and stir gently until combined.•Grease baking dish with olive oil. Spoon mixture evenly into dish, cover with foil and bake until set, 25 to 30 minutes. For a top with some crisp and browned edges, uncover and continue to bake about 5 minutes more.
10. Stuffing can be assembled (but not baked) one day ahead. Keep chilled, covered, then bring to room temperature 30 minutes before baking.