Description
Recreate the iconic Subway Sweet Onion Sauce right at home with this easy, homemade recipe! This sweet, tangy, and slightly spicy sauce is the perfect topping for sandwiches, wraps, salads, and grilled meats. It’s made with simple ingredients, takes only 15 minutes, and tastes just like the original—if not better!
Ingredients
Scale
For the Sauce
- 1 cup sugar
- 1/2 cup water
- 6 tablespoons white vinegar
- 1 1/2 tablespoons red wine vinegar
- 1/2 tablespoon finely minced onion
- 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
Instructions
- Combine Liquids & Sugar – In a saucepan, mix sugar, water, white vinegar, and red wine vinegar. Heat over medium heat, stirring until the sugar fully dissolves.
- Add Flavorings – Stir in finely minced onion, Dijon mustard, mustard powder, sesame oil, and poppy seeds. Mix well to combine.
- Thicken the Sauce – In a small bowl, mix cornstarch with 1 tablespoon water to form a slurry. Slowly pour it into the saucepan while stirring continuously.
- Season & Simmer – Add onion powder, salt, garlic powder, celery seed, paprika, and black pepper. Reduce heat to low and simmer for 3-5 minutes, stirring occasionally.
- Cool & Store – Remove from heat and let the sauce cool completely before transferring to an airtight container. Refrigerate for at least 1 hour before serving.
Notes
- For a thicker sauce, add more cornstarch and simmer for an extra 1-2 minutes.
- For a spicier version, add a pinch of cayenne pepper or hot sauce.
- Store in the refrigerator for up to 2 weeks in an airtight container.
- Shake well before using if refrigerated, as ingredients may settle.
- Prep Time: 5 minutes
- Cook Time: 10 minutes
- Category: Sauce, Condiment
- Method: Simmering
- Cuisine: American