Main Dish

Shiitake Mushroom Croque Monsieur

Shiitake mushrooms replace ham in this classic French café sandwich.

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Thin-capped shiitakes may be available in supermarkets year-round, but the mass-distributed options offer only a hint of how good the mushrooms can be. Look for shiitake that are pale, plump and unwrinkled, with tender stems, and cook at least 10 minutes to remove any astringent flavor. 



  • 4 1/2 Tbs. butter, divided, plus additional soft butter for spreading

  • 1 1/4 pounds shiitake mushrooms, stemmed and sliced

  • 1/2 cup finely chopped shallots

  • 1 1/2 Tbs. all-purpose flour

  • 1 1/4 cups 1% milk

  • 1/3 cup plus 8 tsp. finely grated Parmesan cheese, divided

  • 2 pinches ground nutmeg

  • 8 slices country white bread

  • 1 cup coarsely grated Swiss cheese (3 ounces)


1  Melt 3 Tbs. butter in large nonstick skillet over medium-high heat. Add mushrooms and shallots, and sauté 10 to 12 minutes, or until mushrooms are deep brown. Season generously with salt and pepper, if desired. Transfer to plate to cool.

2  Melt remaining 1 ½ Tbs. butter in heavy medium saucepan over medium-low heat. Add flour and stir until mixture bubbles. Whisk in milk. Boil 1 minute, or until thickened, whisking constantly. Remove from heat. Stir in 1⁄3  cup Parmesan and nutmeg. Season with salt and pepper, if desired. Set aside.

3  Butter 1 side of each of 8 bread slices. Place 4 slices buttered-side down on large baking sheet. Top each with ¼ mushroom mixture, then sprinkle each with ¼ cup Swiss cheese. Top with remaining bread slices, buttered-side up. 

4  Preheat broiler. Heat large nonstick skillet over medium-high heat. Add 2 sandwiches, and cook 3 minutes per side, or until browned. Repeat with remaining sandwiches, and return sandwiches to baking sheet.

5  Spoon sauce over sandwiches, spreading to edges. Sprinkle each with 2 tsp. Parmesan. Broil 3 to 5 minutes, until bubbling and brown in spots, monitoring carefully. Transfer sandwiches to plates with spatula.

Nutrition Information

  • Serving Size per sandwich
  • Calories 622
  • Carbohydrate Content 61 g
  • Cholesterol Content 85 mg
  • Fat Content 33 g
  • Fiber Content 5 g
  • Protein Content 21 g
  • Saturated Fat Content 19 g
  • Sodium Content 823 mg
  • Sugar Content 10 g