Grilled Portobello Steak Sandwiches
In short: Marinated portobello caps grilled until juicy, layered in crusty rolls with sweet caramelized onions, peppery arugula and garlic mayonnaise. It takes about 55 min in total and makes 4 servings.
- Prep
- 20 min
- Cook
- 35 min
- Resting
- 20 min
- Total
- 55 min
- Servings
- 4
- Difficulty
- Easy
- Calories
- 520 kcal
Portobello caps are thick and meaty enough to stand in for a steak in a sandwich, and a quick balsamic marinade gives them a deep savory flavor. They grill in about ten minutes, then go into crusty rolls with slow-cooked onions, arugula and a garlicky vegan mayonnaise. The onions can be cooked in advance, so the sandwiches come together fast. Use a grill, a grill pan or a hot skillet.
Instructions
- Whisk the oil, vinegar, soy sauce, garlic, thyme, paprika and pepper in a shallow dish. Add the mushroom caps, gill side up, spoon some marinade into each and leave for 20 minutes.
- Meanwhile, heat 1 tablespoon of oil in a skillet over medium-low heat and cook the onions with the salt for 20 to 25 minutes, stirring now and then, until deep golden and sweet.
- Stir the mayonnaise, grated garlic and mustard together in a small bowl.
- Heat a grill or grill pan over medium-high heat. Grill the mushrooms for 5 to 6 minutes per side, gill side down first, brushing with the leftover marinade, until tender and charred.
- Slice each mushroom into thick strips. Toast the cut sides of the rolls briefly on the grill.
- Spread the garlic mayonnaise over the rolls and fill with arugula, mushroom slices and a pile of caramelized onions. Serve warm.
Tips
- Scrape out the dark gills with a spoon if you want a cleaner-looking sandwich and a less muddy sauce, though they add flavor.
- Add roasted red peppers, sliced tomato or vegan cheese melted under the broiler for a more loaded version.
Questions and answers
Can I cook portobello mushrooms in the oven?
Yes. Roast the marinated caps gill side up at 220°C (425°F) for 18 to 20 minutes, turning once, until tender and browned at the edges.
Can I make the onions ahead?
Yes. Caramelized onions keep for 5 days in the fridge and freeze well in small portions. Reheat them in a pan before assembling.
How do I stop the mushrooms from getting watery?
Do not wash them under running water, just wipe with a damp cloth. Cook them over high heat so the moisture evaporates instead of pooling.
How long does it take to make Grilled Portobello Steak Sandwiches?
About 55 min in total: 20 min of preparation and 35 min of cooking.
How many calories are in Grilled Portobello Steak Sandwiches?
About 520 kcal per serving, with 12 g of protein, 61 g of carbohydrates and 25 g of fat. These values are estimates.
Nutrition per serving
| Calories | 520 kcal |
|---|---|
| Protein | 12 g |
| Carbohydrates | 61 g |
| Fat | 25 g |
| Fiber | 6 g |
| Sugar | 13 g |
| Sodium | 880 mg |
Estimated values, calculated from the ingredients.
