Smoky Mushroom Burgers with Roasted Garlic Mayo Recipe

Introduction

These smoky mushroom burgers are a delicious vegetarian twist on a classic favorite. With roasted garlic mayo, caramelized onions, and flavorful roasted red peppers, they’re packed with rich, smoky taste perfect for any barbecue or casual meal.

Ingredients

• 4 large flat mushrooms
• 1 tbsp olive oil, plus extra for frying
• 2 roasted red peppers (from a jar), finely chopped
• ½ small pack thyme, leaves picked and chopped
• 50g fresh breadcrumbs
• 1 tbsp sundried tomato paste
• 2 tsp smoked paprika
• 3 red onions, thinly sliced
• 1 tbsp golden caster sugar
• 1 tbsp sherry vinegar
• 3 garlic cloves, unpeeled
• 50g good-quality mayonnaise
• 4 crusty bread rolls (such as ciabatta)
• Salad leaves
• 25g cheddar or Manchego, grated

Instructions

1. Step 1: Heat up the barbecue. To make the garlic mayo, wrap the garlic cloves in a foil parcel and place on a hot spot of the barbecue. Cook for 20 minutes until very soft. Alternatively, bake in a hot oven for 20–30 minutes. Let cool, then squeeze the garlic out of the skins and mash with a fork. Mix the mashed garlic with the mayonnaise and chill until ready to use.
2. Step 2: Remove the stalks from the mushrooms and finely chop them. Heat a drizzle of oil in a pan and fry the stalks until golden and soft. Add the chopped roasted red peppers, thyme, breadcrumbs, sundried tomato paste, smoked paprika, and seasoning. Cook for 5 more minutes, then set aside to cool slightly.
3. Step 3: Rub the mushroom caps with a little oil and season. Spoon the pepper and breadcrumb mixture equally among the mushroom caps. You can chill the stuffed mushrooms for up to one day if preparing ahead.
4. Step 4: In another frying pan, heat a little oil and add the sliced onions. Cook gently for 15 minutes until soft and golden. Add the golden caster sugar, sherry vinegar, and seasoning, then cook for 5 more minutes until the onions become caramelized and sticky. The onions can be stored chilled for up to two days.
5. Step 5: Place the stuffed mushrooms on the barbecue, stuffing side up. Cover with the lid or foil and cook for about 20 minutes until tender and cooked through. Keep an eye on the heat and move mushrooms to an upper shelf if the bottoms start to burn. Also, split and heat the bread rolls on the barbecue.
6. Step 6: To serve, spread each roll with garlic mayo, layer salad leaves, add a stuffed mushroom, spoon on some caramelized onions, and finish with a grating of cheese. Enjoy warm.

Tips & Variations

• Use a smoky paprika or chipotle powder for an extra smoky kick.
• Try swapping the cheddar or Manchego for halloumi slices for a different texture and flavor.
• Make the garlic mayo ahead to let the flavors meld; it can be stored in the fridge for up to 3 days.
• Add a splash of balsamic glaze over the finished burger for extra sweetness and depth.

Storage

Store any leftover stuffed mushrooms and caramelized onions separately in airtight containers in the fridge for up to 2 days. Garlic mayo will keep in the fridge for about 3 days. Reheat stuffed mushrooms gently on the barbecue or in an oven until warmed through. Bread rolls are best fresh but can be toasted before serving if stored overnight.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make these burgers indoors without a barbecue?

Yes, you can cook the mushrooms and onions on a stovetop in frying pans and roast the garlic in an oven. Use a hot grill pan or oven broiler to toast the bread rolls.

Are these burgers suitable for vegans?

To make this recipe vegan, substitute the mayonnaise with a vegan alternative and choose a dairy-free cheese or omit the cheese topping altogether.

Smoky Mushroom Burgers with Roasted Garlic Mayo Recipe

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★★★★★

4.9 from 94 reviews

• Author: Noah
• Total Time: 1 hour 5 minutes
• Yield: 4 servings 1x
• Diet: Vegetarian

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Description

These smoky mushroom burgers feature large flat mushrooms stuffed with a flavorful mixture of mushroom stalks, roasted red peppers, thyme, breadcrumbs, sundried tomato paste, and smoked paprika. They are grilled on a barbecue until tender and served in crusty ciabatta rolls with roasted garlic mayo, caramelised red onions, fresh salad leaves, and a grating of cheddar or Manchego cheese, making for a delicious vegetarian alternative to traditional burgers.

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Ingredients

Scale 1x2x3x

Mushroom Burgers

• 4 large flat mushrooms
• 1 tbsp olive oil, plus extra for frying
• 2 roasted red peppers (from a jar), finely chopped
• ½ small pack thyme, leaves picked and chopped
• 50g fresh breadcrumbs
• 1 tbsp sundried tomato paste
• 2 tsp smoked paprika

Caramelised Onions

• 3 red onions, thinly sliced
• 1 tbsp golden caster sugar
• 1 tbsp sherry vinegar

Roasted Garlic Mayo

• 3 garlic cloves, unpeeled
• 50g good-quality mayonnaise

To Serve

• 4 crusty bread rolls (ciabatta)
• Salad leaves
• 25g cheddar or Manchego, grated

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Instructions

1. Prepare the roasted garlic mayo: Wrap the unpeeled garlic cloves in a foil parcel and position on a hot spot of the barbecue or bake in a hot oven for 20-30 minutes until very soft. Allow to cool, then squeeze the softened garlic out of their skins and mash with a fork. Mix this garlic purée into the mayonnaise and chill until ready to serve.
2. Make the mushroom filling: Remove the stalks from the mushrooms and finely chop them. Heat a drizzle of olive oil in a pan on the barbecue or hob and fry the chopped stalks for a few minutes until golden and soft. Stir in the finely chopped roasted red peppers, thyme leaves, fresh breadcrumbs, sundried tomato paste, smoked paprika, and season with salt and pepper. Cook the mixture for an additional 5 minutes, then set aside to cool slightly.
3. Prepare the mushrooms: Rub the mushroom caps with olive oil and season with salt and pepper. Top each mushroom cap with a quarter of the mushroom filling mixture. You can chill the filled mushrooms for up to 1 day if needed.
4. Cook the caramelised onions: Heat a little olive oil in another frying pan on the barbecue or hob. Add the thinly sliced onions and cook for 15 minutes until soft and golden. Add the golden caster sugar, sherry vinegar, and seasoning, then cook for another 5 minutes until the onions are caramelised and sticky. These can be chilled for up to 2 days.
5. Grill the mushrooms: Place the stuffed mushrooms on the barbecue with the stuffed side facing up. Close the lid or cover with foil and cook for 20 minutes until the mushrooms are soft and cooked through. Monitor the heat to prevent burning and move mushrooms to an upper shelf if necessary.
6. Toast the bread rolls: Split the ciabatta rolls and heat them on the barbecue until warmed through and slightly toasted.
7. Assemble the burgers: Spread a generous amount of the roasted garlic mayo on each bread roll, then layer with salad leaves, a stuffed mushroom, caramelised onions, and a grating of cheddar or Manchego cheese. Serve immediately and enjoy your smoky mushroom burgers.

Notes

• Roasting the garlic on the barbecue infuses the mayonnaise with deep smoky flavor, but an oven can be used as an alternative.
• The stuffed mushrooms can be prepared in advance and chilled to save time on the day of serving.
• Keep an eye on the mushrooms during grilling to avoid burning; moving them to a cooler spot helps manage the heat.
• Feel free to swap cheddar or Manchego for your preferred melting cheese if desired.
• This recipe makes a great vegetarian option for outdoor BBQs and gatherings.

• Prep Time: 20 minutes
• Cook Time: 45 minutes
• Category: Main Course
• Method: Grilling
• Cuisine: British

Keywords: smoky mushroom burgers, vegetarian burgers, grilled mushrooms, barbecue recipes, garlic mayonnaise, caramelised onions, ciabatta sandwich