Rach On The Radio - Mushroom Cheddar Melts

1/2 cup EVOO – Extra Virgin Olive Oil (count to 8 while slowly pouring)
1/3 cup dry sherry (count to 6 while slowly pouring)
1/4 cup Worcestershire sauce (count to 4 while slowly pouring)
Sea salt and coarse black pepper
4 large, firm Portobello mushroom caps (at least 1-inch thick), gills scrapped and caps sliced horizontally into 2 disks
8 slices extra-sharp yellow cheddar cheese
4 brioche rolls, lightly toasted
4 thick slices heirloom tomato
A couple handfuls watercress or other spicy greens
Salt-and-vinegar potato chips

Rach on the Radio - Mushroom Cheddar Melts