I love mushrooms! They add that indescribable umami flavor to everything and Portobello ones add meaty heft as well. I’ve described how I normally roast them in foil packets in a previous post but tonight, I made a variation where I added a garlic, shallot, and balsamic vinaigrette puree to the packets before I roasted them.
Here’s what to gather up to serve 4-5 people:
- 5 large Portobello mushrooms, tops wiped clean and stems and gills removed
- 2 medium shallots, coarsely chopped
- 10-15 cloves of garlic, pre-peeled (go buy it at Costco!)
- Macadamia nut oil, avocado oil, lard, or ghee
- Balsamic Vinegar (I use Trader Joe’s Gold Quality Balsamic Vinegar of Modena)
- Kosher salt
- Freshly Ground Black Pepper
- 5 large pieces of heavy duty aluminum foil (your mushrooms can burn if you use regular aluminum foil)
Here’s what you do:
Preheat oven to 400 F and coarsely chop the shallots and trim the ends of the garlic:

Throw the shallots and garlic into a mini-prep food processor or finely mince by hand, Mr. Yan Can Cook.

Add your choice of fat and vinegar to the minced alliums in a 3:1 ratio of oil to vinegar. Season the vinaigrette mixture with a good sprinkling of salt and freshly ground black pepper.
Place each Portobello mushroom on a piece of foil, stem side up. Lightly coat each ‘shroom with extra virgin olive oil and some salt and pepper. Put a dollop of vinaigrette into each mushroom, spreading until the cap is filled.

Tightly seal each mushroom packet and place on a baking tray. Stick the tray in the oven and roast for ~25 minutes.

Remove mushroom from packets (watch out for steam!) and slice up.
