Caramelized Onion, Lettuce, and Tomato Sandwich

Caramelized Onion and Tomato Sandwich

A couple of weeks ago we had a Dirty Gourmet meeting at Emily’s house, and she made us these Caramelized Onion, Lettuce & Tomato (COLT) Sandwiches for lunch. Since she’s now almost vegetarian, Emily has been looking for a great alternative to her favorite sandwich, the Bacon Lettuce Tomato (BLT). According to Emily, she’s “100% satisfied” with her vegetarian BLT creation. As for me, I haven’t had a BLT in probably 10 years, so maybe my vote doesn’t count, but I also thought it was just as good as the original.

Caramelized Onion and Tomato Sandwich Ingredients

I recently signed up for a Community Supported Agriculture (CSA) produce box, so now I get a bunch of local produce once a week. For those of you who don’t know how a CSA works, the idea is that you buy a subscription to receive a share of what a farm produces. It’s a great way to get local, seasonal produce regularly. I like it because it forces me to try new vegetables that I normally wouldn’t buy. This I received my first box. I got tatsoi, strawberries, blood oranges, fennel, Candy beets, purple kale, arugula, celery, a MacArthur avocado, and a head of red leaf lettuce.

So when Emily came over to work with me this week, I forced her to make me her famous COLT sandwich as an excuse to use my beautiful red leaf lettuce. This is one of those recipes where the quality of the ingredients you use makes all the difference. Come tomato time, I’ll probably make this daily.

As for logistics, you can make the caramelized onions ahead of time and assemble your sandwiches at camp. This way they won’t be soggy. Perishability is always something to consider with camping and picnic food, and this sandwich is less perishable than a BLT. But you still have to think about the mayo, so if you’re going somewhere without a cooler, just get some of those little mayo packets.

Assembling Caramelized Onion and Tomato Sandwich

Caramelized Onion and Tomato Sandwich

Caramelized Onion, Lettuce, and Tomato Sandwich


4 Sandwiches

Prep Time / Cook Time


Activity Guide

Bike Touring, Car Camping, Picnic


  • 1 large onion, sliced
  • 3 tablespoons olive oil
  • 1-2 large tomatoes, sliced into thick slabs
  • 8 leaves of lettuce
  • 4 tablespoons mayonnaise
  • Salt and Pepper
  • 8 slices sourdough bread
  • Salt and vinegar potato chips (Optional)


  • Cutting board
  • Knife
  • Skillet
  • Stove
  • Tongs


At Home or At Camp:

  1. Heat a skillet over medium-low heat, and add olive oil and onions. Let them caramelize for about 15 minutes, and then turn the heat up a bit for the last few minutes to get them a bit crispy.

To Assemble Sandwiches At Camp:

  1. Spread mayonnaise on each slice of bread. Add a slice (or slices) of tomato to cover one half.
  2. Sprinkle the tomato with salt and pepper.
  3. Stack a few crunchy pieces of lettuce on top of the tomato, then add onion, and the second slice of bread.

Note: An optional, though important ingredient to mimic the crunch and saltiness of the missing bacon, is salt and vinegar potato chips. The fancy extra crunchy ones are best.

2 thoughts on “Caramelized Onion, Lettuce, and Tomato Sandwich

  1. Just back from our 8th annual girls camping weekend (which was technically a cabin weekend this year). We always divide up food duties and Saturday lunch was this freakin’ awesome sandwich. I think it is the best sandwich I’ve ever had. Making it again for dinner tonight! BTW….. the chips really aren’t optional. That would be like cake without icing.

    1. That’s so great to hear, Cate! This is one of my favorites as well, especially now that the good summer tomatoes will start coming in.

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