Asparagus and Cheese Souffle

Name: Asparagus and Cheese Souffle
Ingredients: 1 tablespoon vegetable oil; 1/4 cup diced red onion; 1 medium yellow squash, cut into1/4-inch-thick half-moon slices; 1 pound thin asparagus, bottoms trimmed, cut into 1-inch pieces; 1/2 cup roasted red pepper strips; 2 tablespoons thinly sliced scallion greens; 6 eggs; 1/2 teaspoon kosher salt; 1/4 teaspoon freshly ground black pepper; 1 pinch freshly ground nutmeg; 1 cup shredded Swiss cheese; 1/2 cup grated Parmesan; Vegetable oil spray, as needed; Equipment: 9 by 5-inch loaf pan and parchment paper