Roasted Portobello Sandwiches
with Pesto Mayo, Parm Frico & Zesty Potato Wedges
- Wheat
- Soy
- Milk
- Eggs
Portobellos are both juicy and meaty mushrooms, making them the perfect veggie sandwich filler. Our chef’s went all in on Meatless Mondays and built a sandwich around these ‘shrooms: toasted ciabatta are slathered in creamy pesto mayo, then topped with the portobellos, Parm frico, and charred tomato. Plus, no sandwich would be complete without potatoes on the side, which you can dip into any extra pesto mayo. You’ll be saying “this sandwich is Frico delicious” with each and every bite.
Ingredients
12 ounce
Potatoes
¼ cup
Parmesan Cheese
2 unit
Ciabatta
(Contains: Wheat, Soy)
1 unit
Lemon
1 tablespoon
Italian Seasoning
4 tablespoon
Pesto
(Contains: Milk)
2 tablespoon
Mayonnaise
(Contains: Eggs)
1 unit
Tomato
2 unit
Portobello Mushrooms
Not included in your delivery
8 teaspoon (tsp)
Cooking Oil
teaspoon (tsp)
Salt
teaspoon (tsp)
Black Pepper
Nutrition Values
Utensils
Cooking Steps
• Adjust racks to top and middle positions and preheat oven to 425 degrees. Wash and dry all produce. • Cut potatoes into ½-inch-thick wedges. Toss on a baking sheet with a large drizzle of oil, half the Italian Seasoning (you’ll use the rest later), salt, and pepper. • Roast on top rack until browned and crispy, 20-25 minutes.
• While potatoes roast, lightly oil a second baking sheet. Sprinkle Parmesan into two 3-inch-wide circles (four circles for 4 servings) on prepared sheet. • Bake on middle rack until cheese is golden brown and crisp, 6-10 minutes. TIP: Check the cheese often to make sure it doesn’t burn. • Let frico cool on sheet until hardened, then carefully transfer to a papertowel-lined plate
• Meanwhile, using the tip of a spoon, remove and discard black gills from undersides of portobello mushrooms; trim any large stems if necessary. Slice tomato into ½-inch-thick rounds. Zest and quarter lemon. • In a small bowl, combine mayonnaise, pesto, and a squeeze of lemon juice to taste. Season with salt and pepper to taste.
• Drizzle both sides of each mushroom with oil; rub to evenly coat. Season all over with remaining Italian Seasoning, salt, and pepper. Arrange gill sides down on sheet used for frico. • Roast on middle rack until slightly tender, 14-16 minutes.
• Season tomato all over with salt and pepper. • Heat a drizzle of oil in a large, preferably nonstick, pan over mediumhigh heat. Add tomato and cook until lightly browned and slightly softened, 1-2 minutes per side. • Turn off heat; transfer to a plate.
• Halve and toast ciabattas; spread cut sides with half the pesto mayo. Fill ciabattas with mushrooms, tomato, and frico. • Divide sandwiches between plates along with potato wedges; sprinkle potatoes with lemon zest to taste. Serve with remaining pesto mayo and any remaining lemon wedges on the side.
Customer reviews
Review summary
Updated on Dec 2025- Flavor: Many loved the pesto mayo, calling it "delicious" and "awesome"; some found it overpowering or salty.
- Ease of prep: Several noted it took longer than expected, with multiple steps and pans to juggle.
- Suggestions: Consider adding fresh greens or avocado for more substance; some preferred fresh tomatoes over cooked.
- Leftovers: A few mentioned it reheated well the next day, though most found it filling as-is.
- Texture: Some found the mushrooms chewy or rubbery; cooking time and method affected tenderness.
- Portions: Several wished for larger or additional mushrooms to better fit the bun size.
Reviews from our home cooks
Excellent flavors together! My husband particularly raved about the pesto mayo, an excellent addition. I appreciated the tips on preparing the portobellos, since I had never cooked with them before, thanks! A suggestion - would be nice to pair the sandwiches with a salad instead of potato wedges. It ended up being sooo much food for us, would have been nice to have a lighter side.
This may be the best sandwich I have ever eaten! It is certainly the most flavorful sandwich I have made. The pesto mayo, frico, tomatoes and wonderfully seasoned and baked portobello combined to create a total mouthgasm!
These are absolutely awesome. Prep time is a little more than 5 mins but still very quick and so fabulous. The frico is such a great idea. We totally polished off the pesto mayo on our potato wedges. Yummo!! Hello Fresh we are thrilled with our menus and thank you for being so creative for vegetarians.
Next time I'm not going to add as much acid, or maybe none, to the pesto mayo, that or make truffle mayo which is amazing on a portobello sandwich. If I want acid, I may use a bit of aged balsamic vinegar to the portobello mushroom.
A surprisingly satisfying "burger" substitute, but really so much more! The Portabellas are so rich in flavor, texture and immune-boosting properties. The Pesto Mayo was a fabulous touch! I loved learning to make Frico; will definitely do that again! And a side of crispy potato wedges... Hmm.. Hmm... Good!
Super easy recipe that made regular Portobello mushrooms into a delightful new style of sandwich for me to crave.
First time eating a whole portobello mushroom like a burger. Loved the pesto mayo and roasted potatoes. The roasted cheese was different, I'll eat it again though.
Delicious mix of veggies, frico was perfect on top of the portobello and juices made the ciabatta roll soft and delicious. Seasonings on potatoes was also very good and I never thought to put lemon on potatoes but it was really a nice touch.
This was also delicious! I guess I had never eaten portobellos and was surprised to scrape off the gills, but all in all the sandwich was excellent. Flavors were perfect!
This was amazing! I thought it would not be filling but it was just perfect. The pesto mayo was a little salty but it was balanced out with everything else.
