Grilled Cheese with Caramelized Onions, Grainy Mustard, and Gruyère

grilled cheese

Back in the before time, in November of 2018 to be exact, the chef Nancy Silverton hosted a grilled cheese night at Republique here in L.A. Republique — one of the best restaurants in L.A., if not the best (see here) — is the site of Nancy Silverton’s iconic restaurant of yore, Campanile. There, with her then-husband Mark Peel, Nancy would have a regular grilled cheese night which was especially popular because of the bread she used, from her own La Brea Bakery which was next door.

So this grilled cheese night harkened back to the original grilled cheese night and Nancy’s signature grilled cheese — The Nancy — was offered on the menu. I ate it and delighted at the combination of onions (which I remembered as being caramelized but now see were marinated), grainy mustard, and lots of Gruyère.

Sometimes the passing of recipes is like a game of telephone; something gets lost in translation. I’m sure Nancy has good reason for marinating her onions, but in my own attempts to recreate her signature grilled cheese, I started caramelizing the onions.

Whereas I suppose the marinated onions in The Nancy offer up some necessary acid, my caramelized onions lend depth and even more decadence to the proceedings.

The process goes like this: you take two small yellow onions, or one large one, peel and slice them thin then caramelize them slowly in butter and olive oil. Let’s say two tablespoons of each. You start on high heat with a pinch of salt and then, when you’ve got some color (see above), you crank the heat to medium/low and cook, slowly (you should hear a gentle sizzle) for 45 minutes or longer. You want the onions deep, deep golden brown, like below.

Then it’s a simple assembly job.

Bread-wise, I like sourdough. Spread a thick layer of grainy mustard on one side (that’s where you get your acidic pop in this version), add a mound of grated sharp white cheddar (my preferred cheese to the Gruyère; also, you’re more likely to have it around), and then top with the caramelized onions.

It’s a lot, and that’s the point.

To finish, close your sandwiches up, melt 2 tablespoons of butter in a large skillet on high heat. Add the sandwiches, lower the heat to medium-low, and cover.

Cover? That’s Craig’s trick (Craig is my husband if you’re new). His only culinary expertise is grilled-cheese related and this is the extent of it: covering the grilled cheese while it cooks lets the cheese melt.

Proceed for several minutes until the bottom of your grilled cheese is golden brown and most of the cheese has melted. Flip, finish on the other side (you can leave the cover off at this point and crank up the heat a little).

If you’re lucky, some cheese will fall on to the outside of the bread and crisp up along with it (in Italy, it’s called frico).

All in all, this isn’t The Nancy, and I wouldn’t dare call it The Adam. It’s just a grilled cheese with deeply caramelized onions, grainy mustard, and an obscene amount of cheese… aka: the only grilled cheese that matters.

1 thought on “Grilled Cheese with Caramelized Onions, Grainy Mustard, and Gruyère”

Let's dish!

Scroll to Top