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Mushroom and red onion toastie

Name: Mushroom and red onion toastie
Prep time: 15 min
Total time: 15 min
Yield: Serves 1
Ingredients: Oil for frying; ½ red onion, sliced; 80g button mushrooms, halved or quartered if large; A few thyme sprigs, leaves picked, plus extra to serve; Knob of butter, plus extra for spreading; 3 tsp good quality balsamic vinegar; 1 large slice sourdough bread; 50g strong cheddar, grated (see Easy Swaps); 30g blue cheese, slice

By: Jen Bedloe
Former head of food delicious.

Published: 1 Dec 21
Updated: 18 Mar 24

If you’re feeling hungover, our mushroom toastie with red onions, cheddar and blue cheese is the best thing since sliced bread.

Our ultimate fry-up sandwich is stacked with bacon and oozy fried egg.

Easy
December 2021

Test kitchen approved

Serves 1
Hands-on time 15 min

If you’re feeling hungover, our mushroom toastie with red onions, cheddar and blue cheese is the best thing since sliced bread.

Our ultimate fry-up sandwich is stacked with bacon and oozy fried egg.

Nutrition: per serving

Calories: 710kcals
Fat: 51.9g
Protein: 26.2g
Carbohydrates: 32.9g (8.8g sugars)
Fibre: 3.7g
Salt: 2.2g

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Ingredients

Oil for frying
½ red onion, sliced
80g button mushrooms, halved or quartered if large
A few thyme sprigs, leaves picked, plus extra to serve
Knob of butter, plus extra for spreading
3 tsp good quality balsamic vinegar
1 large slice sourdough bread
50g strong cheddar, grated (see Easy Swaps)
30g blue cheese, slice

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Method

Add a splash of oil to a non-stick frying pan, then fry the onion with a pinch of salt for 5 minutes. Add the mushrooms, thyme and the knob of butter, then continue to fry, stirring every so often, until the mushrooms are golden brown. Season again with a little salt and add 2 tsp of the balsamic. Turn the heat down slightly and continue to fry for 2 minutes or so until the onions are nice and sticky. Stir in the remaining 1 tsp balsamic, then set aside in the pan to keep warm.
Heat the grill to medium-high. Toast the sourdough, then butter it and layer on the grated cheese. Put under the grill for 2-3 minutes until melted, then top with the sliced blue cheese and stick back under the grill for 1-2 minutes more until bubbling.
Top with the mushrooms and onions, then serve scattered with a few more thyme sprigs.

Recipe from December 2021 Issue

Nutrition

Nutrition: per serving

Calories: 710kcals
Fat: 51.9g
Protein: 26.2g
Carbohydrates: 32.9g (8.8g sugars)
Fibre: 3.7g
Salt: 2.2g

delicious. tips

Easy swaps: Use up odds and ends of whatever cheese you have to hand. Swap the onion and mushroom for leeks, spring onions or leftover roast vegetables.