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During the summer months, when the tomatoes are plentiful, we eat a lot of tomato sandwiches a/k/a … lycopene overload.  Our sandwiches are usually very simple with just tomatoes, mayo and bread.  I often ask my husband what he wants for dinner and he often replies “a tomato sandwich.”  Traveling husband is very easy to please, especially when it comes to homegrown tomatoes.   For several years he asked me to blog a tomato sandwich, so at long last … I’m sharing the most fantastic, delicious, flavorful, incredible, dreamy, cheesy Outdoor Grilled – Grilled Cheese Sandwich with Heirloom Tomatoes and Pesto recipe.
I think if you’re going to have cheese, have some cheese!  This sandwich is great with lots of cheese.  Creamy brie, slightly salty and sweet Gruyère marry perfectly with our homegrown heirlooms.  I used THIS pesto made from our garden basil and slathered it on thick sliced whole grain bread.  Topped with gobs of cheese and chunks of tomato bathed in balsamic vinegar, well you get the idea.  This is a grilled cheese on steroids, a tomato sandwich from another planet, a fantastic dinner or delightful lunch.  I guess if my husband requests another tomato sandwich for dinner, he might even like this recipe for a nice change.

Grilled Cheese with Heirloom Tomatoes and Pesto
Ingredients
- 1 cup ripe heirloom tomatoes cut into ½ inch chunks
- 1 teaspoon balsamic vinegar
- salt and fresh ground pepper to taste
- 4 thick slices whole grain bread
- 2 ounces Gruyere cheese grated, about ½ cup lightly packed
- 2 ounces brie cheese or fontina cheese, sliced
- ¼ cup prepared pesto
Instructions
- Preheat your gas grill - or indoor grill pan.
- While the grill is heating toss the tomatoes and balsamic together in a small bowl. Season with salt and pepper and set aside (stir occasionally)
- Divide the pesto on one side of each slice of bread.
- Top with the shredded Gruyere and brie slices.
- Turn off the center burner on your grill and turn the other burners down to medium. Place the bread halves, cheese side up, on the grill over the unlit burner.
- Close the lid and grill until the cheese melts and the bread is lightly toasted. This should take about 7-8 minutes depending on the temperature of the grill. If the bread is browning too quickly, move to the cooler part of the grill until the cheese is melted.
- Remove the 4 open face sandwiches to a platter and top with the tomato pieces.
- Sandwich the two sides together and serve immediately.
Recipe Notes
Nutrition
I truly can’t wait to make this again.  What a treat!  What do you put on  your favorite tomato sandwich?  Do you like soft bread or toast?  I know this is getting a little personal – and I won’t hold it against you if you don’t like tomato sandwiches, but you HAVE to give this a try!   Hope you have a fantastic weekend and thanks so much for stopping by!
Tricia
Mary
I adore a tomato sandwich as well, so these beauties are calling to me. I miss my garden when I see your beautiful harvests, but then I remember just how much work it was and I settle for the local markets once again! If I ever make it your direction for a visit, you can bet I’ll come during your gardening season.
Tricia Buice
Come on over Mary – we would love to see you. Hope you are not affected by the flooding and heavy rains out your way. Yes gardens are a lot of work but after sitting at a desk most of the day having a little more exercise is not a bad thing for me or my husband. We adore tomatoes 🙂 Thank you so much for stopping by!
Diane (Created by Diane)
I am just LOVING this sandwich and really need to make one….like now!!!
Tricia Buice
Thanks Diane 🙂 I know you would love it!
Kennedy Cole| KCole's Creative Corner
This looks like such a creative, delicious alternative to the caprese combination! We have so many tomatoes from the garden, and this looks like the perfect way to use em’ up! Thanks for sharing, Tricia! 😀 I’ll definitely be trying this ASAP! 🙂
Tricia Buice
Thanks Kennedy – hope you have a great week. Thanks for stopping by and for commenting!
Beth
I love the combination of cheeses you used. Your sandwiches look terrific – no wonder your husband asks for them!
Tricia Buice
Thanks Beth – he is really just a tomato junkie – he’ll eat them until he turns red! This is a full flavored sandwich especially with the pesto – yummy!
Lorraine @Not Quite Nigella
I’m in North American at the moment (Canada) and I’m eating so many tomatoes and cheese! It’s such a great match 😀
Tricia Buice
Thanks Lorraine – and welcome to North America! Don’t you just love tomatoes 🙂 Have a great trip!
Liz
I made a similar grilled cheese a few weeks ago but used fresh mozzarella. Now I’m dying to try it with Gruyere and brie! Yours looks amazing!
Tricia Buice
Thank you Liz! Hope you have a wonderful weekend 🙂
Mandy
Best grilled cheese I have seen.
Have a beautiful day Tricia.
🙂 Mandy xo
Tricia Buice
You too Mandy – thanks for stopping by!
Betty
Now THAT’S a tomato sandwich! I’m not a huge tomato sandwich fan, but when I do eat one it has to be on really soft white bread that I never buy for anything else, with mayo, salt and pepper. BUT with that gorgeous melty cheese (Brie is my favorite) and pesto, the hearty grain bread is perfect! I think this could actually make a tomato sandwich lover out of me. 🙂
Tricia Buice
Haha Betty – I know what you are saying about soft white bread and mayo – takes me back to the old days 🙂 This is a very full flavored treat – can’t wait to make it again!
Toni | Boulder Locavore
This is really what summer food is all about, isn’t it? There is nothing like a naturally ripe summer tomato and pesto made from one’s own garden. I love the look of this Tricia and it sounds perfect too.
Tricia Buice
Thanks Toni – my husband has requested this sandwich again – big endorsement from him since he likes a plain tomato sandwich most of the time. Hope you have a great weekend 🙂
cheri
Hi Tricia, looks like you are having a supreme crop of tomatoes again this year. Love grilled cheese…..you just made it a whole lot better.
Tricia Buice
Thanks Cheri – the balsamic and pesto really make this a super treat. Have a lovely weekend!
Monica
I don’t eat sandwiches as much as I used to but sometimes I think a great sandwich is like the perfect food. 🙂 I am getting my act together and loading up on fresh tomatoes while they are so good right now. This sandwich, anchored with the tomatoes, looks so divine. I am aching to take a bite of it!
Tricia Buice
I personally do not eat very much bread anymore but in the summer a good tomato sandwich is a must. The fresh basil pesto really brings this sandwich to a whole new level. Have a great weekend!
Becky Green
HEAVENLY!!! 😉 We actually stay away from toasting our sandwiches too much, as it tears up our mouths when we bite into them, but LIGHTLY GRILLED, DOES sound WONDERFUL! 😉 And for Tomato Sandwiches, we used to just add mayonnaise, but all the goodness you’ve added, DOES SOUND HEAVENLY!!!!!!!!!!!! 😉
Tricia Buice
I think this would be great just warmed in the microwave to melt the cheese too. Hope you have a great weekend!
Maureen | Orgasmic Chef
In the summer, when tomatoes are at their best, I’d rather have a sandwich like this than anything else I could think of. I don’t know how to describe it but it’s like eating summer.
Tricia Buice
I think you described it very well Maureen – summer fresh basil pesto and tomatoes – amen! Hope you are feeling much better!
Susan
Such a simple meal but, oh, so delicious! I have some nice juicy tomatoes almost ripe and ready to use for something just like this.
Tricia Buice
You bet Susan – it is summer perfection with fresh basil pesto and the tomatoes – I could eat this every day. Hope you and your family have a very nice weekend.
Vineetha @ Mint and Mimosas
What a fresh delicious dish. With all these farmers markets in full swing, this is the perfect way to use tomatoes you might buy! Adding in the pesto is just the cherry on top!
Tricia Buice
Thanks Vineetha – the pesto really is a wonderful touch. Have a lovely weekend!
sue|theviewfromgreatisland
Why oh why aren’t we neighbors? These are the most exciting looking grilled cheese sandwiches I’ve ever seen!
Tricia Buice
If we were neighbors Sue – I would make this for you and share our tomatoes!
Larry
That is one fine looking sandwich Tricia made special with fresh maters and that great looking bread.
Tricia Buice
Nothing like a great sandwich Larry – hope the travel is going well!
cali @ cali's cuisine
I just happen to have some heirloom tomatoes sitting on my kitchen counter and now they are begging to be used in this recipe. I think I will make paninis tonight – simple yet elegant. Thank you for solving my dinnertime dilemma!
Tricia Buice
I hope you’ll give it a try Cali – this is a keeper! Have a great weekend.
Chris Scheuer
I have to admit, I’m a bit (well, maybe a lot) jealous of your heirloom tomatoes, Tricia. How amazing to make a sandwich like this with tomatoes picked from your own yard!!
This is a super delicious looking sandwich and a simple summer meal at the same time. I love that!
Tricia Buice
Thanks Chris – we have really been enjoying these delicious tomatoes! I am going to miss them when they are gone!
Jennifer @ Seasons and Suppers
I could eat a dozen of these! My absolute favourite grilled cheese 🙂
Tricia Buice
It is tasty beyond words! Thanks for stopping by Jennifer.
Angie@Angie's Recipes
The sandwich must be very tasty with all the fresh quality ingredients.
Tricia Buice
Gotta love cheese and garden fresh tomatoes Angie. Have a wonderful weekend.