Portobello Mushroom Sandwich

This balsamic marinated portobello mushroom sandwiches is one of my favorite lunch recipes! I've added leftover steak to the ones seen in the picture, so feel free to do the same if you have steak or chicken that you need to use, however I'd argue the mushroom is better on it's own! The combination of caramelized onions, balsamic vinegar and feta cheese is (chef's kiss). I am not a huge blue cheese fan, but the feta can easily be replaced by blue cheese in this recipe as well!

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Ingredients:

2 sub rolls or bread of choice

1 yellow onion

2 portobello mushroom caps

¼ cup balsamic vinegar

4 tablespoons olive oil

2 slices of Swiss or mozzarella cheese

1/3 cup feta cheese

2 tablespoons of Mayo (preferably Dukes)

½ cup of Spinach

Instructions:

1. Pre-heat oven to 375 degrees

2. Thinly slice yellow or white onion and place in pan with butter to caramelize on medium-low heat – to truly caramelize in the low heat takes 30+ minutes

3. While oven is pre-heating, marinate the portobello mushroom caps in olive oil and balsamic vinegar, salt and pepper

4. Roast mushrooms for 20-minutes

5. While mushrooms are roasting, toast bread of choice

6. Spread mayo, sprinkle feta cheese, and add toppings such as a handful of spinach, red pepper, tomatoes, and caramelized onions once ready

7. Slice balsamic portobello mushrooms and add to sandwich

Enjoy!