Subway Sweet Onion Sauce

Homemade version of the tangy and sweet onion sauce from Subway.

  • Author: Jessica Pinney
  • Prep Time: 5 minutes
  • Cook Time: 10 minutes
  • Total Time: 15 minutes
  • Category: Sauce
  • Cuisine: American


1 Cup Sugar

1/2 Cup Water

6 Tablespoons White Vinegar

1 1/2 Tablespoons Red Wine Vinegar

1/2 Tablespoon Onion, freshly grated with a microplane

1 Tablespoon Cornstarch

2 Teaspoons Dijon Mustard

2 Teaspoons Mustard Powder

1 Teaspoon Poppy Seeds

1/2 Teaspoon Sesame Oil

1/2 Teaspoon Onion Powder

1/2 Teaspoon Salt

1/4 Teaspoon Garlic Powder

1/4 Teaspoon Celery Seed

1/4 Teaspoon Paprika

1/4 Teaspoon Black Pepper


Add all the ingredients to a sauce pan. Bring it to a boil while whisking constantly.

Let it boil for 5 minutes, then reduce the heat to a simmer for another 5 minutes – whisking the entire time.

After the sauce thickens, remove from heat and allow to cool.

Store in an airtight container in the refrigerator for up to 1 week.