Grandma Weaver's Cheese Souflee - S Clyde Weaver

Ingredients

• 1/4 cup plus 2 Tablespoons Freshly Grated Parmigiano-Reggiano Cheese
• 6 ounces Gruyere Cheese, shredded (2 packed cups)
• 3 tablespoons unsalted butter
• 3 tablespoons all-purpose flour
• 1 1/4 cups heavy cream
• 4 large eggs, separated, plus 3 large egg whites
• 3 tablespoons dry sherry
• 2 tablespoons sour cream
• 1 1/4 teaspoons kosher salt
• 1 teaspoon Dijon mustard
• 1/2 teaspoon dry mustard
• 1/4 teaspoon cayenne pepper
• 1/4 teaspoon cream of tartar