Caramelized Onion and Mushroom Stuffed Baked Brie

stuffed baked brie

I don’t make a lot of appetizers, but the holidays are a great excuse to try out some new ones. And Brie en croute (baked in puff pastry) is one of the best–easy and delicious, but with an impressive presentation!

stuffed baked brie

Preparation can be very simple. Just spread a little jam over the pastry before wrapping and baking and you’re good to go. But if you’ve got the time and inclination, a stuffed Brie is even better. For this version, I used a combination of caramelized onions and sauteed mushrooms–but of course, you can use whatever you like. Credit for the stuffing idea and overall process goes to–visit the site for a cranberry and walnut version.

In this recipe I’m using Mark Bittman’s method for caramelizing onions published in How to Cook Everything: The Basics. Rather than starting the onions in oil or butter, they go into a dry pan with a lid, which steams them until tender. Then, they are allowed to caramelize uncovered with a knob of butter and some seasoning. It might just be my imagination, but I’m convinced that this two-step process is faster (at any rate, it’s less effort) than the traditional method that requires frequent stirring.

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Caramelized Onion and Mushroom Stuffed Baked Brie

Yield: 8

Calories per serving: 330

Fat per serving: 25 g

Carbs per serving: 16 g

Protein per serving: 12 g

Caramelized Onion and Mushroom Stuffed Baked Brie


  • ½ large onion, sliced thinly
  • 2 tbsp butter, divided
  • 8 oz mushrooms, cleaned and sliced
  • 2 cloves garlic, minced
  • 1 tsp dried thyme
  • 1 tsp soy sauce
  • 2 tbsp balsamic vinegar
  • 1 tbsp vermouth or wine
  • Salt and pepper
  • 1 16-oz wheel of Brie
  • 1 sheet puff pastry
  • 1 egg, beaten
  • Toasted baguette slices or crackers to serve


  1. Unwrap the puff pastry and place it on a plate on the counter to thaw. This should take 30-40 minutes. Meanwhile, place the Brie in the freezer to chill it well.
  2. Heat a lidded skillet over medium heat. When hot, add the onions and cover. Cook, stirring occasionally, until the onions soften and begin to brown and stick to the pan. Remove the lid and add 1 tbsp butter, a pinch of salt and a grind of pepper. Continue to cook, uncovered, stirring occasionally, until caramelized. Remove to a bowl to cool.
  3. In the same skillet, melt the remaining 1 tbsp butter. Add the mushrooms, garlic and thyme, and cook until the mushrooms brown, stirring occasionally. When the mushrooms begin to release liquid, add the soy sauce, vinegar, and vermouth or wine. Continue to cook until the liquid evaporates and the mushrooms appear glazed. Taste and add pepper and salt (if necessary). Remove to a separate bowl to cool.
  4. Preheat the oven to 425F. (If desired, spread baguette slices on a baking sheet and toast them in the oven for a few minutes.) Line a baking sheet with a piece of parchment paper.
  5. Remove the Brie from the freezer. Using a sharp knife, score the equator of the wheel, making a cut about 1/8– to ¼-inch deep all the way around. Work a piece of kitchen twine or plain dental floss into the cut, tying the ends together in an overhand knot. Pull the ends in opposite directions (as if you were tightening the knot) to cut through the cheese. Pull the two halves apart.
  6. Unfold the puff pastry on the baking sheet. Place one half of the Brie (rind-side down) on the pastry. Layer the mushrooms and then the onions on top of the cheese. Top with the other half of the Brie, rind-side up.
  7. Brush the puff pastry with the beaten egg. Then, pull the pastry up over the cheese and pinch together the edges to seal it in completely. It’s ok if you need to stretch it a little, or cut off some extra. Flip the Brie over so that it is seam-side down, and brush the outside with the beaten egg. You can decorate the top with extra puff pastry before brushing with the egg, if desired.
  8. Bake the Brie 20-25 minutes until the pastry is golden brown on the outside. The cheese will probably ooze a bit—that’s ok! Let it rest just a minute or two before removing to a cutting board or platter. Serve with toasted bread or crackers.

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