Depending on the size of the vegetables, this recipe makes about four good-sized sandwiches. These make a delicious lunch or light dinner served with a green salad and/or baked fries. The roasted mushrooms and peppers are also excellent on a salad or on their own. 

Marinade: 
1/2 cup extra-virgin olive oil
3 Tablespoons balsalmic vinegar
2 Tablespoons grainy mustard
1 Tablespoon fresh lemon juice
1 teaspoon sea salt
2 cloves garlic, crushed

Ingredients
2 large portobello mushrooms
1 large red bell pepper
Crusty whole grain bread or baguettes
lettuce, tomato slices, sprouts, etc. for serving

To Make: 
1. Combine marinade ingredients in a bowl or large measuring cup.
2. Wash the mushrooms and peppers, slice, and place in a bowl.
3. Pour the marinade over the vegetables and cover bowl with lid or plastic wrap. Set aside for 8-48 hours (allowing the vegetables to marinate for a day or two gives them a chance to really soak up the flavor).
4. Preheat the oven to 400°.
5. Spoon the vegetables onto a baking tray with sides to catch the extra juices, leaving any extra marinade in the bowl.
6. Bake for about 15 minutes, or until the mushrooms are tender.
7. Assemble sandwiches.

If the vegetables are to be used in one meal, use the excess marinade for salad dressing or as a drizzle for other grilled or roasted vegetables. If you have extra vegetables, just place them back in the bowl with the marinade and enjoy them later.