Classic Grilled Cheese with Marinated Onions

Thursday 31 January 2019

We don't always have days when we are wanting a big meal to eat for our suppers in this house.  I think as you get older, your appetites change and you don't eat quite so much as you did when you were younger. 

I can remember back when I was first married, some many years ago, having a full supper and then cooking a box of Kraft Dinner or making a boxed pizza mix with my husband to snack on in the evening.  My how things have changed! 

Not only would I not be hungry enough to eat such a hearty snack before bed these days, but I also would end up suffering all night with acid reflux if I did!  No, ageing is not for the weak!  It comes accompanied with all sorts of delights to experience!

Anyways, I digress.  We don't always want a big meal. Sometimes we only want a sandwich.  There is no need for it to be a boring sandwich however!  (As if I could ever make a boring sandwich!)

This tasty sandwich takes the concept of a simple grilled cheese and infuses it with the flavours of Alsace . . .

You begin with marinating onions in a mix of vinegar, olive oil and seasoning  . . . it doesn't take long to do this, only 15 minutes.  You will want to slice your onions as thinly as you can.  I used my  Essential 5-in-1 vegetable shredder to slice my onions. It is  a really handy tool to have in the kitchen.  Easy to use, clean, store and maintain.  I love it and use it a lot.  You can find out more here.

Once you have the onions marinating, you can slice your cheese.  I like Gruyere cheese, which is a lovely melting cheese.  Gruyere is a melty type of Swiss cheese, with a lovely nutty flavour.  I adore it.

If you can't get it, you can substitute it with Emmenthal, Beaufort, Jarsberg, Comte or Raclette cheese, but do try to get the Gruyere if you can.  Don't use processed Swiss cheese slices.  There is really no comparison.  NO comparison.

You will also need some grainy mustard.  I adore grainy mustard  . . .  with its robust texture and slight heat, it is lovely in any sandwich.

Sour dough bread is best, but any good white loaf will work well.  You do want a sturdy one that will stand up to the filling.

I like to cut my slices about 3/4 of an inch thick . . .

Buttered on the outside with softened butter and spread on the inside with the grainy mustard  . . .

Then topped with half of the cheese, and the marinated onions . . .  and finally the remaining cheese, and then closed in with the other slice of bread . . .

It is then toasted or griddled in a hot skillet, on a grill pan,  or pressed in a panini press, until golden brown on both sides and the cheese is oozingly melty.  Yum!  These are so tasty! 

Yield: 4

Grilled Cheese with Marinated Onions

prep time: 15 minscook time: 15 minstotal time: 30 mins
A very different kind of grilled cheese sandwich.  Simple ingredients put together easily to give  sandwich with real WOW factor!


  • 70ml extra virgin olive oil (1/3 cup)
  • 2 - 3 TBS sherry vinegar
  • (can use white wine vinegar or champagne vinegar)
  • 2 TBS Kosher salt
  • 1 TBS freshly ground black pepper
  • 2 medim brown onions, peeled and very thinly sliced
  • 8 slices of white or whole wheat sour dough bread
  • 62g of whole grain mustard (1/4 cup)
  • 230g Gruyere cheese (8 ounces) cut into very thin slices
  • softened butter


  1. First prepare the marinated onions.  Put the onions into a bowl along with the olive oil, vinegar, salt and pepper  Rub together to combine and then sit aside for about 15 minutes to pickle.
  2. To assemble the sandwiches,  butter each slice of bread on one side only.  Place four slices, buttered side down  and spread the unbuttered side with the grainy mustard.  Top with half of the sliced cheese, trying to keep as much of it inside the edges of the bread as possible. Divide the pickled onions evenly amongst the sandwiches.  Top with the remaining cheese and then the other four slices of bread, buttered sides up.
  3. Toast the sandwiches in a large skillet, or in a panini press until the bread is toasted completely and the cheese has melted.  Cut on the diagonal to serve.  Serve hot.
Created using The Recipes Generator

I served them with a bit of rocket on the side and a garnish of some of the pickled onions we have leftover from Christmas.  This was pure and utter comfort.  There is no other word for it.  I can imagine that if you are the drinking sort it would go down really lovely with a sparkling lager or cider, and maybe even a few potato crisps/chips on the side.  Simple flavours done well and done simply.  You can't beat it!  Bon Appetit! 


  1. When I was little my mom bought a jar of asst.pickles and such ..I would eat the onions and cauliflower;) Yes we change our eating habits for sure..

    1. I always loved the jars of sweet mixed pickles my mother bought Monique. The cauliflower and onion were favourites of us all. There was never enough to satisfy each of our appetites! I always thought they should make jars of just sweet pickled cauliflower and onions! That is one thing I miss over here. Pickles. They do have them, but they are not the same! xo

  2. This is my idea of comfort food! I can picture myself eating this with a nice bowl of tomato soup. I think I have tomorrow's dinner sorted now :-)

  3. Mmm. A couple of nights ago I had a grilled cheese sandwich for dinner. It would have been so much better with marinated onions. My favorite. If I had some in the house, I'd make up a batch -- they keep well for a bit and are fun to add to things. Like, as you just showed me, grilled cheese!

    1. The onions really kick them up a notch Jeanie! xo


Thanks for stopping by. I love to hear from you so do not be shy!

Did you make the recipe as directed? Recipe results are not guaranteed when changes have been made.

Is this comment helpful to other readers? Rude or hateful comments will not be approved. Remember that this website is run by a real person.

Are you here to complain about ads? Please keep in mind that I develop these recipes and provide them to you for free. Advertising helps to defray my cost of doing so, and allows me to continue to post regular fresh content.

Thanks so much for your understanding! I appreciate you!