Gruyere with Caramelized Onions Panini

Somewhere around the 45-minute mark, as I was still diligently stirring the slowly caramelizing onions and oregano, my curiosity over whether this loooooong process was truly going to be worth it began to turn into resentment. This was a grilled cheese sandwich, for crying out loud. The simplest of all sandwiches. My husband had long since finished eating his lunch. I was hungry!

It was so worth it. Tom Colicchio, forgive me for ever doubting you.

'wichcraft, by Tom ColicchioThe recipe was created by the Top Chef king himself, from his new sandwich cookbook, ‘wichcraft: Craft a sandwich into a meal–and a meal into a sandwich (the same one I gave away last week in The Grilled Cheese Pageant). I thought I’d close out National Grilled Cheese month with his Gruyère with Caramelized Onions sandwich on rye bread. I’ve got to tell you – until now, my Bacon, Cheddar & Grilled Tomatoes Panini had been my all-time favorite grilled cheese. I still love that one…but I do believe I love this Gruyère and onions one just a little bit more. And I’ll tell you why.

Caramelized onions

It’s somewhat similar to my French Dip Panini, in that both aim to replicate the flavors of French Onion soup. But, of course, Tom’s doesn’t have any roast beef or jus. Just sweet yellow onions caramelized really slowly with fresh oregano and grilled with nutty Gruyère cheese on rye bread. The combination is very simple and insanely delicious. Just like in the soup it was inspired by, the Gruyère stretches between your mouth and sandwich with each bite. And those onions! To say they’re like candy might be overstating things, but not by much. Ignore all my whining about how long it took to make them – good things do indeed come to those who wait. Better yet, prepare them ahead of time and then when you’re ready to grill your panini they’ll all come together in a matter of minutes.

Gruyere with Caramelized Onions Panini

Gruyère with Caramelized Onions Panini
Adapted from ‘wichcraft: Craft a sandwich into a meal–and a meal into a sandwich

Serves 4


  • 4 tablespoons extra-virgin olive oil
  • 4 medium yellow onions, halved and cut lengthwise into 1/8″ slices
  • 2 tablespoons chopped fresh oregano, or 1 tablespoon dried Sicilian oregano
  • Kosher salt and freshly ground black pepper
  • 8 oz. Gruyere cheese, grated
  • 8 slices rye bread


In a skillet over medium-high heat, add the olive oil and onions and stir vigorously to avoid scorching. Add the oregano and season with salt and pepper. Continue stirring until the onions have a deep brown color. Reduce the heat and continue to cook until the onions are soft, 30 to 45 minutes. Set aside.*

Preheat the panini grill to medium-high heat (375°F).

For each sandwich: Place 1/4 of the cheese on a slice of bread. Follow with a generous amount of onions. Close the sandwich and place on the panini grill. Grill for 4-5 minutes until the cheese is completely melted and the bread is toasted with golden grill marks. Serve immediately and enjoy!

* Either use the onions immediately to make the panini or refrigerate them for up to 1 week.


KathyPanini Happy, online since 2008, is more than just a sandwich blog. Here, you'll find hundreds of my original panini recipes, my guide to choosing a panini press and a whole lot of other creative uses for the panini press.
~ Kathy Strahs
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  1. Mindy wrote:

    Oh my gosh! This looks amazing–I can’t wait to get back to my panini grill in the US in July!

    Posted 4.28.09 Reply
  2. HoneyB wrote:

    This looks and sounds so yummy! I know what book is going to be on my to buy list next!

    HoneyB’s last blog post..Of burgers and fries

    Posted 4.28.09 Reply
  3. Dani wrote:

    oh what i wouldn’t give for that right now!!! 🙂

    Dani’s last blog post..#58) Chewy Ginger Cookies

    Posted 4.28.09 Reply
  4. Maris wrote:

    I love caramelized onions and I think this might be MY favorite panini of yours too!

    It is funny though, how much effort we put into the simplest recipes. I think though, that they usually turn out to be worth it in the end 🙂

    Maris’s last blog post..Chocolate Ganache & A Sweet Giveaway

    Posted 4.28.09 Reply
  5. grace wrote:

    i’m glad you stuck it out and didn’t give in to your resentment. 🙂

    grace’s last blog post..squawk!

    Posted 4.28.09 Reply
  6. Kate wrote:

    What a fantastic idea!

    Posted 4.28.09 Reply
  7. Digigirl wrote:

    That looks sooo yummy! I love carmelized onions anyway. I’ve got that book on my wishlist!

    Digigirl’s last blog post..Sticky Toffee Pudding

    Posted 4.28.09 Reply
  8. lo wrote:

    I could totally get into this sammich.
    I think caramelized onions are always worth the effort 🙂 … bet this book is loaded with great ideas like this. Yum.

    lo’s last blog post..Fight Back Fridays: The Daffodil Principle

    Posted 4.28.09 Reply
  9. Jen Yu wrote:

    Oh Ma Gah! That is one of my favorite soups transformed into one of my favorite food forms. You are a genius. How bleeping gorgeous is that?! I *heart* you. *gush*

    Jen Yu’s last blog post..daring bakers: cheesecake

    Posted 4.28.09 Reply
    • Kathy wrote:

      You’re so kind! I’ll have to defer the genius designation to Chef Tom but maybe I’m just a little bit smart for deciding to try his recipe 🙂

      Posted 4.28.09 Reply
  10. Melissa wrote:

    Definitely worth the wait for caramelized onions and then to pair them with Gruyere in a panini? *Dying*

    Posted 4.28.09 Reply
  11. Esi wrote:

    Mouth watering! Yet another to add to the list.

    Esi’s last blog post..Pork Souvlaki

    Posted 4.28.09 Reply
  12. I’m a recent convert to caramelized onions. I always liked them, but never made batches to keep on hand until recently. This is a sandwich I’d definitely make over and over again.

    Lydia (The Perfect Pantry)’s last blog post..Syrian spice, a Pantry Special (Recipe: chicken shish kabob)

    Posted 4.28.09 Reply
  13. Neecy wrote:

    If you don’t want to go through the effort to carmelize the onions next time – but still want a French Onion Soup feel to the panini – give this a shot: thinly slice a white onion, put it in a glass baking dish with a tablespoon of butter and about a cup of dry white wine. Braise in a 350 oven until the onions absorb the liquid, about 40 minutes. Use in your Gruyere panini as you would the carmelized version.

    Posted 4.28.09 Reply
    • Kathy wrote:

      Thanks a lot for that tip, Neecy. I imagine the onions would be just as sweet and delicious without having to monitor them over the stove. Good to know!

      Posted 4.28.09 Reply
  14. Pam wrote:

    Drool worthy!

    Pam’s last blog post..Asian Chicken Breasts

    Posted 4.29.09 Reply
  15. I saw your mention by Tastespotting via Twitter! Congrats! That is always exciting. Plus, your main photo is awesome.

    I was just in Williams-Sonoma and saw Tom’s book, which as you know is really awesome. The first thing I thought of was, “This is the book Kathy gave away in Grilled Cheese Pageant!” 🙂

    GrilledShane’s last blog post..I Love Grilled Cheese: CHEDD’S gourmet grilled cheese

    Posted 4.29.09 Reply
  16. Emily wrote:

    That looks incredible! Glad to know it was worth the effort.

    Emily’s last blog post..WEEK 21: Patty Melt Pizza

    Posted 4.30.09 Reply
  17. kris wrote:

    Oh yum! My vegetarian dd is loving the sight of this sandwich!

    kris’s last blog post..Make-Do Flaky Biscuits

    Posted 4.30.09 Reply
  18. The long, slow cook of caramelized onions has always put us off from a recipe. We’ve read how some people have cooked them for up to 4 hours! That’s dedication. Your quicker method is one to remember.

    The Duo Dishes’s last blog post..A Belly Full of Buitoni

    Posted 4.30.09 Reply
  19. Dragon wrote:

    This sandwich is making me drool all over my keyboard. You owe me a new keyboard. 🙂

    Dragon’s last blog post..Apple and Pomegranate Tart

    Posted 4.30.09 Reply
    • Kathy wrote:

      LOL – might be easier to mail off a bib 🙂 You’re too kind!

      Posted 4.30.09 Reply
  20. Hayley wrote:

    That looks delicious! I love paninis and gruyere is my favorite cheese ever. I’ve read reviews of that cookbook that talked about how long some of the sandwiches take to prepare, but most agreed that it was worth the time and effort. Looks yummy!

    Hayley’s last blog post..Maman and Gourmand Smoothie/Shake Recipe Contest!

    Posted 4.30.09 Reply
  21. Gabi wrote:

    Guess what I am doing for lunch today! HA! Lovely!

    And I dig the Gruyere cheese on it! But no rye bread in sight in my kitchen. So I will have to try this with my home made Sourdough – unfortunately Chicago’s wild yeast, not San Francisco’s, mind you!

    Gabi @ Mamaliga

    Gabi’s last blog post..Bloggers Unite For Hunger and Hope

    Posted 5.1.09 Reply
  22. Jamie wrote:

    I absolutely love a great French onion soup and the idea of turning it into a sandwich is just brilliant! I am so into caramelized onions these days and this is one sandwich I really want to make – and eat!

    Jamie’s last blog post..A LOVE AFFAIR WITH ITALY

    Posted 5.2.09 Reply
  23. Gaby wrote:

    just made this last night… it was sooooo yummy!

    Gaby’s last blog post..Salmon Fillets over Couscous

    Posted 5.4.09 Reply
  24. marguerite wrote:

    YUM!!!! I would LOVE this sammie!

    marguerite’s last blog post..Cinco de Mayo – Chile Relleno Casserole & Carnitas

    Posted 5.5.09 Reply
  25. Anna wrote:

    Oh man, that sounds good. I might try it with Gouda, though….and some spinach.

    Posted 5.6.09 Reply
  26. Jude wrote:

    Gruyere is probably my favorite cheese for grilled sandwiches. So nice how it melts with a bit of heat.

    Jude’s last blog post..Injera – Ethiopian Sourdough Flatbread

    Posted 5.10.09 Reply
  27. Kevin wrote:

    What a tasty panini. I just can’t get enough of those caramelized onions.

    Posted 5.30.09 Reply
  28. Kim wrote:

    Oooh, I just bought some gruyere to fix some savory galettes. Love this sandwich, Kathy. Nothing like a good sandwich.

    Kim’s last blog post..Charleston Benne Wafers with Blueberries and Cream

    Posted 6.16.09 Reply
  29. Christine wrote:

    Maybe it’s just lunchtime looming, but that panini has my stomach rumbling! Yummmm.

    Posted 7.16.09 Reply
  30. rita wrote:

    I’m practically drooling as I type this…. Looks amazing and can’t wait to try it!

    Posted 10.2.10 Reply
  31. Aisha Alomair wrote:

    I have to hand it to you. This panini rocks my socks off!! I make it every single day and I am addicted to it, Love the oregano with the onions, just mixes right, keep up the good work

    Posted 10.29.10 Reply