140min 4 ppl
Creamy Mushroom Thermidor
55 minutes
4 people
Medium31–60 min or 7–12 steps
55 min · 12 steps
Medium: 31–60 min or 7–12 steps
420 kcalper person
Protein 18g
Carbs 14g
Fats 32g
About this dish
Portobello caps roasted until they weep, then packed with a Gruyère-laced béchamel sharpened with Dijon, tarragon, and a splash of dry white wine - the Thermidor treatment classically reserved for lobster, applied here to mushrooms with equally luxurious results. A final blast under the grill leaves the cheese blistered and deeply golden.
Allergy Info
Dairy, Gluten, Sulphites
Diet Info
Vegetarian
Ingredients
Fresh Produce
- Portobello mushroomsstems removed and reserved8 large
- Shallotsfinely minced2 medium
- Garlicfinely minced3 cloves
- Chestnut mushroomsfinely diced150 g
- Fresh tarragonfinely chopped1 tbsp
- Fresh flat-leaf parsleyfinely chopped1 tbsp
- Lemon juicefreshly squeezed1 tsp
Dairy & Eggs
- Unsalted butter3 tbsp
- Whole milkwarmed200 ml
- Double cream100 ml
- Gruyèrefinely grated80 g
- Parmesanfinely grated30 g
Dried Goods
- Plain flour2 tbsp
Spices & Seasonings
- Cayenne pepper0.5 tsp
- Fine sea salt1 tsp
- Black pepper0.5 tsp
- Flaky sea saltto finish1 pinch
Oils & Condiments
- Dry white wine100 ml
- Dijon mustard1.5 tsp
- Olive oil2 tbsp
Utensils
- Baking tray
- Sauté pan
- Whisk
- Cheese grater
Method
1
Preheat the oven to 200°C. Finely dice the reserved portobello stems. Mince the shallots and garlic. Chop the tarragon and parsley. Warm the milk in a small saucepan over low heat until steaming; set aside. Combine the Gruyère and Parmesan in a small bowl; set aside.
Approx. 10 minutes
2
Brush the portobello caps on all sides with olive oil, season with fine sea salt and black pepper, and place gill-side down on a baking tray.
Approx. 3 minutes
3
Roast the mushroom caps for 12 minutes until they begin to release their liquid and shrink slightly. Remove from the oven, flip gill-side up, and tip out any accumulated liquid - this prevents a watery filling.
Approx. 12 minutes
4
Melt the butter in a wide sauté pan over medium heat until foaming. Add the shallots and cook for 3-4 minutes, stirring frequently, until soft and translucent.
Approx. 4 minutes
5
Add the garlic, diced portobello stems, and diced chestnut mushrooms. Cook over medium-high heat for 6-8 minutes, stirring occasionally, until all moisture has evaporated and the mushrooms are deeply golden.
Approx. 7 minutes
6
Pour in the white wine and cook for 2-3 minutes until completely reduced and the pan is nearly dry.
Approx. 3 minutes
7
Reduce the heat to medium-low, sprinkle the flour over the mushroom mixture, and stir constantly for 1-2 minutes to cook out the raw flour taste.
Approx. 2 minutes
8
Add the warm milk in a steady stream, stirring continuously, and cook for 3-4 minutes until the sauce is thick and smooth with no floury taste remaining.
Approx. 4 minutes
9
Stir in the double cream, Dijon mustard, cayenne, and lemon juice. Cook for 1-2 minutes, then remove from heat and fold in half of the cheese mixture along with the tarragon and parsley. Taste and adjust seasoning.
Approx. 2 minutes
10
Divide the filling generously among the gill-side-up mushroom caps. Top each with the remaining cheese mixture.
Approx. 3 minutes
11
Return to the oven and bake for 10 minutes until the filling is bubbling at the edges and the cheese is melted.
Approx. 10 minutes
12
Switch the oven to the grill setting and grill for 2-3 minutes until the tops are deeply golden and blistered. Finish with a pinch of flaky sea salt and serve immediately.
Approx. 3 minutes
