- 6 Tablespoons butter, divided
- 2 medium leeks (white part only), sliced lengthwise, then sliced crosswise
- 1 (3.5-ounce) package shiitake mushrooms, stems removed, sliced
- 1 medium red bell pepper, diced
- 1(10-ounce) package frozen chopped spinach, thawed, squeezed dry
- 3 Tablespoons Stonewall Kitchen Caramelized Onion Mustard
- 8 ounces White Cheddar cheese, grated
- 1 cup grated Parmesan cheese, divided
- 12 large eggs
- 2 cups heavy whipping cream or half and half
- 1 teaspoon salt
- 1/2 teaspoon freshly ground pepper
- 1 cup panko bread crumbs
- Melt 2 Tablespoons butter in large skillet over medium-high heat. Add leeks, shiitake mushrooms, and red pepper, sauté for 3-4 minutes. Stir in spinach. Cook 2-3 minutes or until all liquid is evaporated, then cool to room temperature. Stir in Cheddar cheese and 1/2 cup of Parmesan cheese.
- In large mixing bowl whisk eggs, Caramelized Onion Mustard, cream or half and half, salt and pepper.
- Spread spinach mixture in bottom of greased 3-quart baking dish. Pour egg mixture over spinach. (Can be made a day ahead if refrigerated and covered.)
- Before baking, melt remaining 4 Tablespoons of butter. Combine with panko, remaining 1/2 cup of Parmesan cheese and salt and pepper to taste. Sprinkle over egg mixture.
- Bake uncovered in preheated 350 degree F oven for 35-40 minutes, or until knife inserted in center comes out clean.