This Tomato and Onion Sauce or Salad, or Molho a Campanha, is a delicious condiment or side dish for meat, seafood, or veggies. Make it ahead and enjoy it this week!
Tomato and Onion Sauce or Salad is so easy to make, but really tastes amazing. It's called Molho a Campanha in Portuguese, which translates to a sauce of vinegar or vinaigrette. The tomatoes and basil are bright and fresh and the onions are mellowed out in the sweet and tangy vinaigrette. It compliments so many things. My family pairs it primarily with steaks. However, you could use it with chicken, fish, roasted potatoes, grilled veggies, on salads, on soups, and so much more!
Background: In Brazil, flavors are kept simple and authentic. My understanding of the cuisine is to not overcomplicate it, but rather accentuate the natural flavors of the ingredients. Therefore, simple sides and condiments are used to enhance foods. My mother in law, who grew up in Portugal and Brazil has been making this delicious Tomato and Onion salad since I can remember. I love it so much that now I make it whenever I grill meats as well.
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Tomato and Onion Salad Ingredients and Swaps
- Tomatoes, large - The easiest option for tomatoes for dicing in this recipe is to go with beefsteak. These are the largest and easiest to hold and cut. See my tip for dicing them. You can substitute with vine tomatoes or plum tomatoes. If you go any smaller, such as with cherry tomatoes or grape tomatoes, then simply quarter them.
- Onion, medium - I used yellow onion for this. You can also use vidalia, red onion, or shallots. Green onions will also work for the flavor, but will give you a different texture that won't be as crunchy.
- Basil leaves - Basil really is the ideal fresh herb for this recipe. However, if you don't have it, you can use fresh cilantro or fresh parsley leaves for the freshness.
- Salt - Any salt that you have is fine for this, but you don't want a salt that is too coarse, as it may not dissolve and blend into the vinaigrette.
- Black Pepper - Freshly ground black pepper is best for this since there are so few ingredients. However, already grounded black pepper works just fine.
- White Wine Vinegar - I like white wine vinegar so that the colors come from the tomatoes and basil rather than the vinegar. You can substitute in red wine vinegar, apple cider vinegar, or even rice wine vinegar. If you do not have any vinegar, you could also use about 3-4 limes, depending on how much juice they produce.
This tomato salad is best enjoyed freshly made. You can make it a few hours ahead and it will still take fresh. You can store it in the fridge for up to 5 days in an airtight container, but the fresh plump tomatoes will start to break down and the onion will start to soften so you won't have that crunch.
For the onion, if you really have onion-resistant eaters, then you can dice the onion a few hours early and soak in cold water in the refrigerator to mellow out any harsh onion flavor.
For the basil, keep basil leaves in the refrigerator attached to the stem for as long as possible before plucking the leaves and cutting them. Basil oxidizes very fast, meaning it will start to darken in color and lose that beautiful vibrant green color. Save the cutting of the basil until you are ready to mix the salad. Once mixed with the vinegar, the vinegar will help to slow the oxidation and preserve the green color.
How to Make Recipe
Dice the tomato and save the juices, placing both in a large mixing bowl. Dice the onion the same size as the tomato or slightly smaller. Also place both in the mixing bowl.
Slice the basil leaves by stacking them on top of each other, rolling them, then slicing them thin.
Place them in the bowl with the tomato and onion.
Add the vinegar, salt, and pepper. Stir and enjoy!
Tomato and Onion Sauce Salad FAQs
The best tomato for this tomato and onion salad or sauce is beefsteak or vine tomato. They will be the juiciest and meatiest to hold up to the vinegar. You can use plum tomatoes, but they will be a bit more delicate and sweeter. Cherry and Grape tomatoes can be used, but will have more skin texture and will be more work to cut.
See above Ingredient Substitutions section for types of onions to use. However, if you absolutely cannot use onions, then here are a few alternatives. You could use diced cucumber, red bell pepper, or green bell pepper. These will not give you the same flavor, but will still give the crunch. You could also mince a garlic clove into this. This will be more for the pungent flavor vs. texture, so you will need to add either more tomatoes or one of the other alternatives.
This tomato and onion sauce is fantastic served with or on top of grilled steak, chicken, fish, shrimp, potatoes, or other grilled veggies. Try adding it with Brazilian Picanha. Or how about with simple Rice and Feijão: Brazilian Beans Recipe? Or go the full Feijoada: Rice and Beans Brazilian Style with Meat!
If you need to store this tomato and onion salad for more than an hour, you should do so in the refrigerator for best results and safety. Store it in an airtight container for up to 5 days.
Be sure to check out the web story for this Tomato and Onion Salad (or Sauce!).
Tomato and Onion Sauce or Salad
- 2 Tomatoes, large
- 1 Onion, medium
- 30 Basil leaves
- 1 teaspoon Salt
- 1 teaspoon Black Pepper
- ¾ to 1 cup White Wine Vinegar
- Dice the tomato and save the juices, placing both in a large mixing bowl. Dice the onion the same size as the tomato or slightly smaller. Also place both in the mixing bowl.
- Slice the basil leaves by stacking them on top of each other, rolling them, then slicing them thin. Place them in the bowl with the tomato and onion.
- Add vinegar, starting with ¾ cup. If your tomatoes and onion were large, you may want to add the remaining ¼ cup. The ideal amount is to be able to cover all of the tomatoes and onions, so it's more like a sauce. Add the salt, and pepper. Stir and enjoy!