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French Onion Soup Stuffed Mushrooms

French Onion Soup Stuffed Mushrooms
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French Onion Soup Stuffed Mushrooms combine the rich, caramelized onion flavor of classic French onion soup with earthy mushrooms, all topped with melted Gruyère and Parmesan cheese. This elegant and easy-to-make appetizer is perfect for parties, cozy snacks, or as a vegetarian-friendly starter that delivers an irresistible blend of savory flavors and comforting textures.

Ingredients

Scale

Mushrooms and Vegetables

  • 16 large cremini or white mushrooms (firm caps)
  • 2 medium sweet yellow onions, thinly sliced
  • Stems from the mushrooms, finely chopped
  • 2 cloves garlic, minced

Fats and Broth

  • 2 tablespoons butter (or olive oil for vegan option)
  • 1/4 cup beef or vegetable broth

Herbs and Seasonings

  • 1 teaspoon fresh thyme leaves (or rosemary/sage for variation)
  • Salt, to taste
  • Black pepper, to taste
  • Optional: pinch of red pepper flakes

Cheese

  • 1/2 cup grated Gruyère cheese
  • 1/4 cup grated Parmesan cheese
  • For vegan variation: use vegan cheese or nutritional yeast instead

Instructions

  1. Prepare the Mushrooms: Clean the mushrooms carefully and remove the stems, setting the caps aside for stuffing. Finely chop the stems to use in the filling mixture, ensuring no waste and extra flavor.
  2. Caramelize the Onions: In a skillet, sauté the thinly sliced onions in butter over low heat, stirring frequently, until they become deep golden brown and fragrant. This slow caramelization develops the signature French onion soup sweetness and depth.
  3. Cook the Filling: Add the chopped mushroom stems and minced garlic to the caramelized onions. Cook until tender. Pour in the broth and sprinkle fresh thyme. Simmer the mixture until most of the liquid evaporates and it thickens into a savory filling perfect for stuffing.
  4. Stuff the Mushrooms: Spoon the prepared onion filling generously into each mushroom cap, packing it well to ensure every bite is flavorful and hearty without overfilling to avoid cheese spillage.
  5. Add Cheese and Bake: Top each stuffed mushroom with a mixture of grated Gruyère and Parmesan cheese. Bake in a preheated oven at 375°F (190°C) until the cheese melts, bubbles, and browns to a golden crust, about 15-20 minutes.

Notes

  • Choose firm, dry mushrooms to hold stuffing better and provide a meaty texture.
  • Be patient when caramelizing onions; slow cooking develops rich flavor and avoids bitterness.
  • Do not overfill mushrooms; leave space so the cheese can brown evenly.
  • Use fresh herbs like thyme for brightness and aroma.
  • Serve warm for the best flavor and texture experience.
  • To make vegan, substitute butter with olive oil and use plant-based cheese or nutritional yeast.
  • Leftovers store well in the fridge up to 3 days and reheat gently in the oven.

Nutrition

Keywords: French onion soup, stuffed mushrooms, appetizer, vegetarian, baked mushrooms, caramelized onions, Gruyère cheese, easy appetizer, party snack

Find it online: https://marygourmet.com/french-onion-soup-stuffed-mushrooms/