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This is the story about how I bought a loaf of bread and made one of the best sandwiches of all time.
This story is a tale of how onions sizzle and sweeten. How baby bellas brown to perfection. And the way my heart pitter-patters when melted cheese stretches between two halves of a sandwich.
Alight! Now i’ve got your attention.
The leading characters: Ms. Sweet Caramelized Onions and Mr. Meaty Baby Bella Mushrooms.
Oh and of course the real reason we’ll all be scarfing down loads of these paninis. Melty, ooey, gooey provolone cheese.


Mushrooms after they’ve been cooked for 10 minutes. Next we add the red pepper flakes and black pepper. Add the flour and cook for 1 minute. Add the mushroom broth (or beef broth) one tablespoon at a time (4 tablespoons in total).
Sprinkle with parsley. Hear the sizzle. The butter as it slowly takes in the flavors of garlic and thyme. The touch of heat with the red pepper flakes. You want a bite. You know you do.
Lets make a panini!
Into the panini press it goes! Or in my case… my George Foreman. But that’s not really fun to say.
Caramelized Onion Baby Bella Panini Melt
Ingredients
To make the caramelized onion + mushroom filling:
- 2 tablespoons EACH: unsalted butter AND olive oil
- 1 and 1/2 large onions or 2 medium sliced into 1/4 inch thick slices
- 1 tablespoon sugar
- 1/4 teaspoon thyme
- 1 – 2 tablespoons minced garlic
- 1 teaspoon Worcestershire sauce
- 8 oz fresh baby Bella mushrooms sliced into 1/4 inch thick slices
- 1/2 teaspoon black pepper
- salt to taste
- 1/4 – 1/2 teaspoon red pepper flakes or more to taste
- 1 teaspoon flour
- 1/4 cup mushroom broth or beef broth
- 2 tablespoons minced parsley
To make the panini:
- 5 – 1 oz. slices provolone cheese cut in half
- 10 slices of fresh french bread
- Cooking spray
Instructions
- To make the caramelized onion + mushroom filling:
Preheat a large skillet on medium heat. Add the butter and olive oil. When the butter is completely melted, add the onions. Let the onions cook down for 5 minutes. Add the sugar and let the onions continue to cook for 15 more minutes. Stir periodically allowing the onions to brown but not burn. Add the garlic, thyme, and Worcestershire sauce and let cook for another 2 minutes. Add the mushrooms. Stir and mix everything together until well incorporated. Continue to cook for another 10 minutes. Add the black pepper, red pepper flakes, and flour. Cook for 1 minute. Add the mushroom broth (or beef broth) in 1 tablespoon at a time. Wait until the onion/mushroom mixture absorbs the liquid before adding the next tablespoon. Once the 4 tablespoons are added, turn off stove remove from heat and add the parsley. - To make the panini:
To assemble the sandwich, place a halved slice of cheese on a piece of bread. Add desired amount of filling and top with another halved slice of cheese and another slice of bread. Spray one side of the sandwich with cooking spray and place that side down on the panini press. Spray the other side and press sandwich for 3 – 4 minutes of until the preferred toast level is achieved.
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Hello! Where can I find the actual recipe that includes how much of each ingredient you used? Maybe it’s because I’m using an iPad but this information isn’t showing up. Thank you!
Really good and pretty easy. We didn’t have the bread but had Tortillas. Yum!
Thanks for the recipe
So good. I didn’t have provolone so I used gouda on nom nom