This is a mayo-ketchup sauce with sweet relish, garlic, cilantro, and a splash of apple cider vinegar — mixed in one bowl in under ten minutes. It works on burgers, as a dipping sauce for fries, or thinned slightly as a salad dressing. If you want something better than bottled burger sauce without any real effort, this is it.
The technique that matters
The only technique here is whisking, but it matters more than it sounds. Minced garlic and cilantro need to be worked into the mayo thoroughly — if you just stir loosely, you get pockets of sharp raw garlic instead of an even flavor throughout. Whisk hard for about 30 seconds until the mixture looks uniform and slightly glossy. Then refrigerate it for at least 15 minutes before serving. The apple cider vinegar needs that short rest to mellow and pull the other flavors together; straight out of the bowl it tastes a little sharp. Use real mayonnaise, not the light version — light mayo has more water and makes the sauce thin and slightly bitter once the vinegar goes in.
Troubleshooting
- Sauce tastes too sweet: The sweet relish and ketchup together can tip sweet depending on your brand of ketchup. Add a small extra splash of apple cider vinegar — about a quarter teaspoon at a time — and re-whisk until it balances out.
- Garlic flavor is too harsh: Raw minced garlic is punchy. If you mince it very fine and let the sauce sit in the fridge for 30 minutes instead of 15, the sharpness softens considerably. Alternatively, use the flat of a knife to crush the garlic into a paste before mincing — it distributes more evenly and tastes less aggressive.
- Sauce is too thick to spread: Different mayo brands vary in thickness. Stir in half a teaspoon of water at a time until it reaches a consistency you can spread easily without tearing the bun.
- Cilantro is turning the sauce bitter after a day: Fresh cilantro breaks down quickly once cut. If you are making a batch to last several days, stir the cilantro in fresh each time rather than storing it in the sauce.
- Sauce looks separated after refrigerating: This is just the vinegar settling. Give it a quick stir before serving and it comes back together immediately.
Storage and reheating
Store the sauce in an airtight container in the refrigerator for up to five days. The flavor actually improves on day two once the garlic and vinegar have had more time to settle in. Do not freeze this sauce — mayonnaise breaks when frozen and thawed, leaving you with a grainy, separated mess that cannot be fixed by stirring. There is no reheating needed; serve it cold or at room temperature straight from the fridge.
Burger and Fry Sauce (Ready in 10 Minutes)
Equipment
- Medium mixing bowl
- Whisk
- Airtight container for storage
Ingredients
- ⅔ cup real mayonnaise 160g
- ⅓ cup ketchup 80g
- ¼ cup sweet relish 60g
- 1 heaping tablespoon fresh cilantro finely minced, about 5g
- 1 teaspoon apple cider vinegar
- 1 tablespoon garlic minced, about 3 cloves / 10g
- 1 teaspoon onion powder
- ¼ teaspoon ground black pepper
Instructions
- In a medium bowl, combine the mayonnaise, ketchup, and sweet relish. Whisk until smooth and evenly blended.⅔ cup real mayonnaise, ⅓ cup ketchup, ¼ cup sweet relish
- Add the minced garlic, cilantro, onion powder, apple cider vinegar, and black pepper. Whisk vigorously for about 30 seconds until the mixture looks uniform and slightly glossy, with no visible pockets of garlic or cilantro.1 heaping tablespoon fresh cilantro, 1 teaspoon apple cider vinegar, 1 tablespoon garlic, 1 teaspoon onion powder, ¼ teaspoon ground black pepper
- Transfer the sauce to an airtight container and refrigerate for at least 15 minutes before serving. This rest allows the apple cider vinegar to mellow and the flavours to come together.
Notes
Nutrition
FAQ
Can I make this sauce ahead of time?
Yes, and it is actually better made a day ahead. The flavors — especially the garlic and vinegar — meld together overnight in the fridge and the sauce tastes more cohesive than it does freshly mixed.
Can I substitute dill relish for sweet relish?
You can, but the sauce will taste noticeably more tangy and less balanced. If you use dill relish, reduce the apple cider vinegar by half to compensate.
I don’t like cilantro — what can I use instead?
Leave it out entirely. The sauce holds together fine without it. Fresh flat-leaf parsley is a neutral swap if you want some green herb flavor without the soapy note that cilantro has for some people.
How much sauce does this recipe make?
The recipe serves 6, which works out to roughly two tablespoons per person. If you are using it as a dip for fries rather than just a burger spread, plan on doubling the batch.
Can I use garlic powder instead of fresh garlic?
Yes. Use half a teaspoon of garlic powder in place of the tablespoon of minced fresh garlic. The flavor will be milder and slightly sweeter, which some people prefer in a sauce like this.
Is this the same as In-N-Out Thousand Island spread?
It is similar in structure but not identical. In-N-Out’s spread uses no cilantro and a different vinegar ratio. This version has a sharper, more herb-forward flavor — think of it as a looser cousin rather than a direct copycat.
What to cook next
- Animal Style Burger Recipe
- Perfect In-N-Out 2×2 Copycat
- Veggie Sauce Burger Perfection
- Ultimate Avocado Bacon Smash Burger