Ciabatta filling with chestnuts and pancetta (garnish)

Ingredients:

• 80 g butter
• 220 g pancetta, cut into 0.5 cm cubes.
• 2 large onions, finely chopped
• 2 carrots, peeled and finely chopped
• 3 stalks celery, finely chopped
• 2 tbsp chopped fresh rosemary leaves
• 3 cloves garlic, chopped
• 2 x 200g cans of canned peeled whole chestnuts, coarsely broken
• 1/4 cup chopped fresh parsley leaves
• 450 g of yesterday's ciabatta, cut into 2 cm cubes.
• 2/3 tbsp. freshly grated parmesan
• 1 cup (or more) canned low-sodium chicken broth
• 2 large eggs, beaten

Preparation:

1. Preheat oven to 175°C.
2. Grease a 14 x 10 x 2-inch (37.5 x 25 x 5 cm) glass baking dish. Melt 2 tablespoons of butter in a large heavy-bottomed skillet over medium heat. Add the pancetta and cook until golden, about 10 minutes. Using a slotted spoon, transfer the pancetta to a large bowl.
3. In the same skillet, melt the remaining butter over medium heat. Add the onion, carrot, celery, rosemary, and garlic. Sauté until the onion is very soft, about 12 minutes. Gently stir in the chestnuts and parsley. Transfer the onion mixture to a large bowl with the pancetta.
4. Add the bread and Parmesan and stir to distribute evenly. Add enough broth to moisten the mixture. Season with salt and pepper to taste. Stir in the eggs.
5. Transfer the filling to the prepared pan. Cover with foil, greased side down, and bake until heated through, about 30 minutes.
6. Then remove the foil and continue baking until the top is golden brown and crispy, about 15 more minutes.