INGREDIENTS
1 1/4
lbs Portobello mushroom caps
2 tsp
Thyme, fresh
2
Yellow onions, large
3/4 cup
Lower-sodium vegetable broth
2 tbsp
Dijon mustard
1/2 tsp
Horseradish, prepared
1 tsp
Lower-sodium soy sauce
1 tbsp
Vegetarian or vegan worcestershire sauce
1/4 tsp
Black pepper, freshly ground
1/4 tsp
Kosher salt
2 1/2 tbsp
Olive oil
4
whole-wheat hoagie rolls, whole-wheat
2 tsp
Butter, unsalted
4
Swiss cheese, very thin
1/3 cup
Sherry, dry