June 18, 2026 · 10 min

Philly-Style Mushroom Sandwiches with Dijon Mayo and Seasoned Potato Wedges

Dinner10 min904 cal / serving

Get ready for a sandwich that’s big on flavor and completely meatless. We’re piling sautéed mushrooms, peppers and onions onto a toasted baguette, then topping it all with melted mozzarella and a creamy Dijon mayonnaise. It’s a satisfying, veggie-forward take on the classic Philly cheesesteak that will have you coming back for more.

Alongside, we’re serving up crispy seasoned potato wedges roasted to golden perfection. The bold steak spice blend adds a savory kick that ties everything together. Whether you’re a longtime vegetarian or just looking to switch up your dinner routine, these sandwiches are sure to hit the spot.


Recipe details

Dinner10 min904 cal / serving2 servings

Nutrition per serving

Calories904 kcalProtein21.8 gFat49.7 gCarbs88.3 gSugar28.1 gFiber5.8 gSodium5980 mg

Dietary labels

Gluten-free: noLactose-free: noDairy-free: no

Allergen check

Gluten / wheat: containsMilk / dairy: containsEgg: containsFish: not detectedShellfish: not detectedPeanut: not detectedTree nuts: not detectedSoy: containsSesame: not detectedMustard: containsCelery: not detectedSulphites: not detectedLupin: not detectedMolluscs: not detected

Values are calculated per serving from ingredient amounts and the ingredient nutrition reference per 100g. Allergen and diet labels use available ingredient metadata and name matching; always check product labels for strict diets or allergies. Some ingredient amounts or nutrition values were incomplete, so this is marked as a partial estimate.


Ingredients

Cremini Mushrooms8 ounce Cremini MushroomsView ingredient guide
Yellow Onion1 unit Yellow OnionView ingredient guide
Long Green Pepper1 unit Long Green PepperView ingredient guide
Yukon Gold Potatoes12 ounce Yukon Gold PotatoesView ingredient guide
Fry Seasoning1 tablespoon Fry SeasoningView ingredient guide
Mayonnaise4 tablespoon MayonnaiseView ingredient guide
Dijon Mustard2 teaspoon Dijon MustardView ingredient guide
Demi-Baguette2 unit Demi-BaguetteView ingredient guide
Mozzarella Cheese0.5 cup Mozzarella CheeseView ingredient guide
SaltSaltView ingredient guide
PepperPepperView ingredient guide
Olive Oil2 teaspoon Olive OilView ingredient guide

Instructions

  1. Preheat the oven to 450°F (230°C) with racks in the top and middle positions. Wash and dry all produce. Cut the potatoes into ½-inch-thick wedges. Halve, peel and thinly slice the onion. Halve, core and thinly slice the green pepper. Trim and slice the mushrooms into ¼-inch-thick pieces.
  2. On a baking sheet, toss the potato wedges with a drizzle of olive oil, half the Fry Seasoning (reserve the rest for later), salt and pepper. Spread in a single layer. Roast on the top rack until golden brown and tender, 20-25 minutes.
  3. Meanwhile, heat a drizzle of olive oil in a large pan over medium-high heat. Add the onion, green pepper and remaining Fry Seasoning. Cook, stirring occasionally, until softened and lightly browned, 5-7 minutes. Season with salt and pepper. Transfer to a plate and wipe out the pan.
  4. In a small bowl, combine the mayonnaise and Dijon mustard. Season with salt and pepper. Slice the baguettes lengthwise without cutting all the way through. Open them like a book and place cut sides up on a second baking sheet. Toast on the middle rack until lightly golden, 3-5 minutes.
  5. Heat a drizzle of olive oil in the same pan over medium-high heat. Add the mushrooms and cook, stirring occasionally, until browned and crispy, 5-7 minutes. Season with half the Bold & Savory Steak Spice (use all for 4 servings) and salt. Cook, stirring, until fragrant, about 30 seconds. Stir in the mushroom stock concentrate and a splash of water. Cook until the liquid has evaporated and the mushrooms are saucy, 1-2 minutes. Return the cooked peppers and onions to the pan and stir to combine.
  6. Spread the inside of each toasted baguette with half of the Dijon mayo (or use all for extra sauciness). Fill the baguettes with the mushroom-veggie mixture and sprinkle mozzarella cheese on top. Return the baking sheet to the oven and bake until the cheese melts, 2-3 minutes. Serve the sandwiches alongside the potato wedges, with the remaining Dijon mayo on the side for dipping.

Recipe Tips

For extra crispy mushrooms, avoid overcrowding the pan and cook in batches if necessary.

If you prefer a spicier kick, add a pinch of red pepper flakes when cooking the peppers and onions.

To make the sandwiches even more indulgent, use all the Dijon mayo on the baguettes instead of reserving some for dipping.

FAQ

Can I use a different type of mushroom?

Yes, you can substitute cremini mushrooms with white button mushrooms, portobello caps (sliced) or a mix of wild mushrooms for a different flavor.

What can I use instead of demi-baguette?

If you don’t have demi-baguettes, you can use regular baguettes (cut into portions), hoagie rolls or even crusty Italian rolls. Adjust toasting time as needed.

Can I make this recipe vegan?

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

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