- 1/2 cup extra virgin olive oil (EVOO)
- 1/3 cup dry sherry
- 1/4 cup Worcestershire sauce
- Sea salt and coarse black pepper
- 4 large, firm portobello mushroom caps (at least 1-inch thick), gills scraped and caps sliced horizontally into 2 disks
- 8 slices extra-sharp yellow cheddar cheese
- 4 brioche rolls, lightly toasted
- 4 thick slices heirloom tomatoes
- A couple of handfuls watercress or other spicy greens
- Dijon mustard or other mustard of choice
- Salt-and-vinegar potato chips
Pour the EVOO (count to 8 while slowly pouring), sherry (count to 6 while slowly pouring), Worcestershire sauce (count to 4 while slowly pouring) and pepper into a dish and mix with your fingers or a whisk. Turn each mushroom disk a few times in the sauce as you add to the dish; season with sea salt. Let marinate for 30-45 minutes, turning occasionally.
Pre-heat a grill or grill pan over medium-high heat. Grill the mushrooms, turning once, until well marked, 4-6 minutes.
Make four stacks in this way: mushroom disk, cheese slice, mushroom disk and cheese slice. Place on the grill until the cheese melts, 1 minute. Transfer the stacks to the roll bottoms and top with the tomato slices; season with salt and pepper. Add the greens. Slather the bun tops with the mustard and set in place. Serve with the chips.