Shells with Mushrooms, Peas & Bacon from Italian Comfort Food by The Editors of Saveur

Ingredients

• 1 cup grated Parmigiano-Reggiano, plus more for serving
• 1 lb. medium pasta shells
• 2 tbsp. unsalted butter
• 6 oz. portobello mushrooms, cut into 1″ pieces
• 1 cup fresh or frozen peas
• 4 slices bacon, cut crosswise into ¼″ strips
• 1 cup chicken stock
• 2 tbsp. extra-virgin olive oil
• Kosher salt and freshly ground black pepper, to taste
• 1 small yellow onion, finely chopped