Food Recipes Portobello Patty Melts 5.0 (1) Add your rating & review Portobello mushroom caps stand in for meat in this vegetarian take on patty melts, which will satisfy even the staunchest meat lover. If you're looking for something to serve alongside, oven fries or sweet potato wedges would be a delicious pairing. By Liz Mervosh Liz Mervosh Elizabeth Mervosh is a product tester and recipe developer for the Meredith Food Studios in Birmingham, Alabama. Highlights: * Went to work at Meredith Food Studios in 2017 * It houses test kitchens for Southern Living, Real Simple, Food & Wine, People, and Health * Went to culinary school at The Culinary Institute of America * Got her start working in restaurants Real Simple's Editorial Guidelines Updated on September 14, 2022 Print Rate It Share Share Tweet Pin Email Photo: Greg DuPree Hands On Time: 40 mins Total Time: 45 mins Yield: 4 serves Jump to Nutrition Facts Ingredients ½ teaspoon smoked paprika ¼ teaspoon freshly ground black pepper ¼ cup olive oil, divided ½ teaspoon kosher salt 8 portobello mushroom caps 1 yellow onion, thinly sliced 4 tablespoons unsalted butter, softened 8 sourdough bread slices ¼ cup Dijon mustard, divided 8 ounces fontina cheese, shredded (about 2 cups) 2 cups packed baby arugula Cornichons, for serving Directions Preheat oven to 450°F. Stir paprika, pepper, 3 tablespoons oil, and salt in a small bowl. Rub mushrooms with mixture and arrange, gill sides down, on a baking sheet. Bake until tender and lightly browned, about 20 minutes. Meanwhile, heat remaining 1 tablespoon oil in a large skillet over medium-high. Add onion and cook, stirring often, until softened and lightly browned, 10 to 12 minutes. Transfer onion to a bowl, reserving skillet. Spread ½ tablespoon butter on 1 side of each bread slice. Divide 1 tablespoon mustard among unbuttered sides of 4 bread slices. Top each with half the cheese. Layer with arugula, onion, mushrooms, and remaining cheese. Top with remaining 4 bread slices, buttered sides up. Cook 2 sandwiches in reserved skillet over medium, flipping once, until cheese is melted and bread is golden brown, 4 to 5 minutes per side. Repeat with remaining sandwiches. Serve with cornichons and remaining 3 tablespoons mustard. Rate it Print Nutrition Facts (per serving) 775 Calories 47g Fat 62g Carbs 20g Protein Show Full Nutrition Label Hide Full Nutrition Label Nutrition Facts Calories 775 % Daily Value * Total Fat 47g 60% Saturated Fat 21g 105% Cholesterol 97mg 32% Sodium 1497mg 65% Total Carbohydrate 62g 23% Total Sugars 14g Protein 20g *The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.