Roasted Portobello Burgers with Sweet Potato Fries and Tomato-Onion Jam

Get ready for a burger that’s bursting with umami and fresh flavors. These roasted portobello mushroom burgers are the perfect meatless alternative, featuring tender, savory mushrooms topped with melted mozzarella, a sweet and tangy tomato-onion jam and crisp lettuce. The basil aioli adds a bright, herby finish that ties everything together.

Serve these satisfying sandwiches with homemade sweet potato fries for a complete meal. The fries get extra crispy when roasted on a preheated baking sheet and any leftover aioli makes a fantastic dipping sauce. This recipe is sure to become a weeknight favorite.

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Ingredients

2 unit Portobello MushroomsView ingredient guideLike ingredientDislike ingredient

2 unit Roma TomatoView ingredient guideLike ingredientDislike ingredient

1 unit Red OnionView ingredient guideLike ingredientDislike ingredient

1 unit Sweet PotatoesView ingredient guideLike ingredientDislike ingredient

2 unit Brioche BunsView ingredient guideLike ingredientDislike ingredient

0.5 cup Mozzarella CheeseView ingredient guideLike ingredientDislike ingredient

1 head Boston LettuceView ingredient guideLike ingredientDislike ingredient

1 sprig BasilView ingredient guideLike ingredientDislike ingredient

2 tablespoon MayonnaiseView ingredient guideLike ingredientDislike ingredient

2 tablespoon Olive OilView ingredient guideLike ingredientDislike ingredient

unit SaltView ingredient guideLike ingredientDislike ingredient

unit PepperView ingredient guideLike ingredientDislike ingredient

Instructions

1. Preheat the oven to 400°F. For extra crispy fries, place a baking sheet in the oven while it preheats. Peel the sweet potato and cut it into 1/2-inch matchsticks (like French fries). Toss the sweet potato sticks with 1 tablespoon olive oil, salt and pepper. Spread them on the hot baking sheet and roast for 20 minutes, tossing halfway through, until golden brown and crispy.
2. While the fries roast, prepare the vegetables. Core and seed one tomato, then finely chop it. Thinly slice the other tomato crosswise. Halve, peel and thinly slice the red onion. Drizzle the portobello mushrooms with 1 tablespoon olive oil and season with salt and pepper. Place them cap-side up on the baking sheet with the sweet potato fries and roast for 10-12 minutes, until tender. (Keep an eye on them-they’ll be done before the fries!)
3. Meanwhile, make the tomato-onion jam. Heat 1 tablespoon olive oil in a medium pan over medium heat. Add the sliced onion and chopped tomato. Cook, stirring often, until the mixture becomes jammy, about 10-15 minutes. If the jam gets too thick, add a splash of water. Season with salt and pepper.
4. While the jam cooks, separate the head of Boston lettuce into leaves. Slice the brioche buns in half horizontally. Top each bun half with shredded mozzarella cheese, then place them in the oven for about 5 minutes, until the cheese is melted and bubbly.
5. Make the basil aioli. Stack the basil leaves, roll them into a cigar and thinly slice into ribbons (chiffonade). In a small bowl, combine the basil ribbons, mayonnaise and a pinch of salt and pepper. Stir until well mixed.
6. Assemble the burgers: Spread each brioche bun half with basil aioli. Place a roasted portobello mushroom on the bottom bun, then add a few slices of fresh tomato, a generous spoonful of tomato-onion jam and a lettuce leaf. Top with the other bun half. Serve the burgers with the crispy sweet potato fries on the side. Enjoy!

Recipe Tips

FAQ

Can I use a different type of mushroom?

Yes, large cremini or king oyster mushrooms can be substituted for portobello, but adjust roasting time as needed.

How do I store leftovers?

Store the components separately in airtight containers in the refrigerator for up to 2 days. Reheat the mushrooms and fries in the oven to maintain crispiness.

Can I make this recipe vegan?

To make it vegan, use vegan brioche buns, dairy-free mozzarella and vegan mayonnaise. The rest of the ingredients are plant-based.