Name: Herbed Onion Salad Dressing
Ingredients: ½ cup cider vinegar; 1½ cups sugar; 1 large onion, cut into wedges; 2 teaspoons salt; 1 teaspoon celery seed; 1 teaspoon ground mustard; ¼ teaspoon each dried basil, marjoram, oregano and thyme; ¼ teaspoon dried rosemary, crushed; ¼ teaspoon pepper; 2 cups vegetable oil

Why it works: Onion and mustard match in chemistry and in kitchens. They rank in the top 4% of all ingredient pairs, and 9,243 recipes mention both. Both carry 2-isopropyl-3-methoxypyrazine, which smells earthy, pea. The science ↓

Explore the science

The flavor team

The pairs that carry this dish. Each one is judged two ways: how much aroma chemistry they share, and how many recipes mention both.

Onion + mustardtop 4% of all pairs

Aroma overlapstrong

Mentioned together9,243 recipes

Shared aroma: 2-isopropyl-3-methoxypyrazine (earthy, pea).
Basil + marjoramtop 1% of all pairs

Aroma overlapstrong

Mentioned together688 recipes

Shared aroma: terpineol (pine, woody).
Celery + mustardtop 3% of all pairs

Aroma overlapmoderate

Mentioned together4,160 recipes

Shared aroma: guaiacol (smoky, sweet).
Celery + marjoramtop 3% of all pairs

Aroma overlapstrong

Mentioned together615 recipes

Shared aroma: beta-phellandrene (minty, terpene).
Celery + basiltop 3% of all pairs

Aroma overlapstrong

Mentioned together811 recipes

Shared aroma: myristicin (spice, warm).

Ranks compare each pair with 20,000 random ingredient pairs on CompKitchen. How we score pairs

What each ingredient does

Cider vinegar: Provides the acidity that gives the dressing its tangy flavour.
Sugar: Adds sweetness that balances the acidity of the vinegar and onion.
Onion: Contributes savoury flavour and aroma, blended into the dressing base.
Vegetable oil: Supplies fat that emulsifies with the vinegar base to thicken the dressing.
Celery seed: Adds a warm, aromatic celery flavour to the dressing.

The step that matters

Adding the oil. Oil must be added gradually in a steady stream while the blender runs. Pouring it in too fast prevents the oil from dispersing into tiny droplets, so the emulsion fails to thicken properly.

Flavor stand-ins for the basil

How well each one fits the dish's main ingredients (cider, vinegar, sugar, onion, celery, mustard, marjoram):

Thymebetter flavor fit
Tarragonbetter flavor fit
Allspicebetter flavor fit
Basilthe original

Fit is the average pairing score against cider, vinegar, sugar, onion, celery, mustard, marjoram. Candidates are from the same food group and used in at least 100 recipes. This compares flavor only: it does not check the job the ingredient does in the dish (bulk, moisture, acidity, structure).

“What each ingredient does” and “The step that matters” were written by Claude from this recipe’s own method and reviewed in samples by CompKitchen.

Herbed Onion Salad Dressing

The recipe

Ingredients

Directions

Make the dressing

Store