Truffled Mushroom and Gruyere Toasted Sandwich

I’ve gone to town on the toastie! Here is my recipe for a gourmet veggie toastie with a twist – chestnut mushrooms cooked in truffle sauce, a touch of garlic and cream and a good helping of cave aged Gruyere which has a refined flavour, one that’s developed over a year of maturing. Good old cheddar works too! Served with a dollop of truffle mayo on the side.


Like many kids growing up in the 1980s, a cheese toasted sandwich was probably one of the first things I could make independently. In fact, aged nine, I opened up a bistro in my tree house – my younger brother was my best (only) customer – and on my menu were Coke floats, sundaes, banana splits and of course, toasties. When I left home, I practically lived off these during my first year of university and things often got creative. I’d end up using leftover Bolognese ragu with mozzarella and basil leaves, sometimes even leftover Indian takeaway went in – saag aloo with chutney but let’s not go there.


I still love an oozing toastie but you can never find any decent vegetarian ones out and about. So I’ve created this gourmet toastie inspired by my roots. Time for another flash back. When I was 16 years old, my first ever job was working in a delicatessen. With dribble at the corners of my mouth, I would marvel at all the gourmet products I’d sell every Saturday. More often than not I used my minimum wage earnings to buy some of these incredible sounding ingredients. One thing I relished was my first ever tango with truffles. I couldn’t afford the pure black truffles but I did manage to splash out on a jar of white truffle sauce, used to stir into pasta or on bruschettas. These days you can buy white truffle sauce in most of the main supermarkets. Having only embraced vegetarian cooking for the last 3 years or so, using truffles in this recipe got me thinking and I’m sure it’s debatable… are truffles vegan? Effectively they’re mushrooms, right and I think they probably are classed as vegetarian but arguably not vegan because, as with honey, there is some animal input used in the process. Although, I’ve read not all truffles are found by pigs.

I have used white truffle sauce in this recipe as a “cheat” – it’s basically a rich and luxurious blend of champignon mushrooms, white truffles and cream. You don’t need pure truffles, this sauce will give you a lovely creamy truffle flavour without the cost. (Be careful though if you are a vegetarian because some of the sauces contain non-vegetarian cheese like Parmesan.)


I’ve also used an extra special type of Gruyere cheese in this recipe, which I found at my local market. It’s aged for much longer than usual Gruyere and has a deeper flavour. Cave-aged Gruyere cheese doesn’t contain any animal rennet so it’s suitable for veggies but you can use any cheese really, I just love this particular flavour combination which goes well with both mushrooms and truffles.

This special toastie deserves to be served up with something equally as decadent, a dollop of truffle mayo on the side. And for a slightly salty and creamy crust, spread some butter and sea salt crystals on the outside of your toastie sandwich bread before toasting. It’s really good served with a glass of Chablis. Oh how times have changed! Back at uni it was Lambrini.


Truffled Mushroom and Gruyere Toasted Sandwich

Serves 2

4 slices of good-quality white bread

100g cave-aged Gruyere, grated (or regular Gruyere)

7 – 8 chestnut mushrooms

2 tsp salted butter

2 tsp white truffle sauce (optional)

2 tsp double cream

½ clove crushed garlic

Olive oil

Sea salt and black pepper

Truffle Mayo:

2 tbsp shop-bought or homemade mayo

½ tsp truffle sauce


  • Make the truffle mayo first by simply mixing the truffle sauce with the mayo and a crack of black pepper – pop in a little dish and place to one side
  • Finely slice the mushrooms and fry in some olive oil or butter until soft but not brown. Then add half a clove of crushed garlic and fry for a further minute.
  • Remove from heat and then add the truffle sauce and double cream and stir. Place to one side.
  • Spread butter lightly on the outside of each piece of bread. If the butter you’re using isn’t salted already, sprinkle the buttered bread with some sea salt
  • Split the mushroom mixture in half and fill the centre of the sandwich along with half of the grated cheese. Keep the filling away from the outside of the bread so that the filling doesn’t spill out and burn during cooking. (But then, if you like a slightly caramelised edge, then go hell for leather with the filling!)
  • To toast your toastie, either: use a toastie maker; or grill the sandwich (melt the centre first under the grill and then grill each side of the bread and press down each time you turn the sandwich); or fry the sandwich, each side for a few minutes until pale brown, in a frying pan with a little extra olive oil


Here’s how I toasted mine… using this Croque Monsieur maker we picked up at a French car boot over a year ago for one Euro!




One thought on “Truffled Mushroom and Gruyere Toasted Sandwich

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s