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Subway Sweet Onion Sauce

Name: Subway Sweet Onion Sauce
Prep time: 5 min
Cook time: 10 min
Total time: 15 min
Ingredients: ½ cup (120ml) cold water; 6 tbsp white vinegar; 2 tbsp red wine vinegar; 1 drop sesame oil (up to 2 drops); 2½ tsp Dijon mustard; ¾ tsp fresh onion juice (use a garlic press); 1 cup (200g) granulated sugar; 1 tbsp arrowroot; 1 tbsp minced onion flakes; 2½ tsp mustard powder; ½ tsp celery seed; 1 tsp poppy seed; 1 tsp salt; ¼ tsp garlic salt (plus 1/8 teaspoon); ¼ tsp paprika (plus 1/8 teaspoon); ¼ tsp black pepper

Calories: 56.5|Fat: 0.3|Carbohydrates: 13.6|Protein: 0.2 | 15

Recipe
What You Need
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Missing Subway’s sweet onion sauce? Make it at home in 15 mins—lasts forever! Perfect for sandwiches. Easy, tasty copycat recipe.

homemade sweet onion sauce, glossy and golden, drizzling over a fresh Subway-style sandwich. The sauce has a smooth, velvety texture with tiny specks of onion flakes and poppy seeds. Shot on a marble countertop with natural lighting, fresh lettuce, tomatoes, and turkey visible in the sandwich.

This popular Subway Sweet Onion Sauce has been replaced by Sweet Onion Teriyaki. If you wish to enjoy this delicacy just mix all the ingredients and simmer. Don’t worry if you’re missing an ingredient as I’m sure you’ll still appreciate the taste.

Why You’ll Like It

Nostalgic flavour – Just like Subway’s original sweet onion sauce you remember.
Better than substitutes – No more settling for teriyaki or other sauces—this is the real deal.
Quick & forever useful – Ready in 15 minutes, lasts for months, and lifts any sandwich to restaurant-quality.

Tips for the Perfect Sweet Onion Sauce (Subway Copycat)

Onion Juice Shortcut: Grate an onion and squeeze the pulp, or use ½ tsp onion powder in a pinch.
Taste Adjustment: Add more sugar for sweetness or vinegar for tang. Celery and poppy seeds add texture but aren’t essential.
Smoother Sauce: Blend after cooling for a silky texture.
Make-ahead Tip: Double the batch and freeze in small jars for future use!

What You Need

Ingredients in Sweet Onion Sauce at Subway

Key Must-Have Ingredients:

✅ Sugar (for sweetness) – 1 cup (200g) granulated sugar
✅ White Vinegar (for tang) – 6 tbsp white vinegar + 2 tbsp red wine vinegar
✅ Dijon mustard (for depth) – 2½ tsp Dijon mustard
✅ Salt & pepper (for balance) – 1 tsp salt+ 1⁄4 tsp black pepper
✅ Thickener (arrowroot or cornstarch) – 1 tbsp arrowroot
✅ Water – 1/2 cup or 120ml drinking cold water

Other Ingredients:

Sesame oil – (1 -2 drops) Only 1-2 drops are used, so it’s subtle. Skipping it won’t ruin the sauce.
Red wine vinegar – (2 tbsp) If you don’t have it, just use all white vinegar (total 8 tbsp).
Celery seed – (1/2 tsp) Adds a slight earthy note but isn’t critical.
Poppy seeds – (1 tsp) Mostly for texture; can be left out if unavailable.
Mustard powder – (2 1/2 tsp) If you already use Dijon, this can be reduced or skipped.
Garlic salt – (1⁄4 tsp plus 1/8 teaspoon) Can sub with regular salt + a tiny bit of garlic powder.
Paprika – (1⁄4 tsp plus 1/8 teaspoon) Adds mild smokiness, but isn’t essential.

How to Make Subway’s Sweet Onion Sauce

1. Combine the ingredients by whisking them all together.
2. Bring the mix to a boil in a small saucepan over medium-high heat. Whisk frequently to avoid burning.
3. Lower the heat and simmer, whisking until the mixture thickens.
4. Let it cool and place it in the fridge, consuming it within one month, or freeze it.
5. Serve: Drizzle over a chicken sandwich with tomatoes and crisp lettuce.

Storage Instructions

Refrigerator: Keeps well for 1 month in an airtight container.
Freezer: Store for 3+ months—thaw overnight in the fridge before using.

Serving Suggestions

Perfect for sandwiches, wraps, burgers, and salads.
Drizzle over grilled chicken or roasted veggies.
Use as a dipping sauce for fries or spring rolls.

More Sauces and Dressings:

Health Info

Servings: You will get 1 cup of sauce, making 16 servings (1 tablespoon each).

NUTRITION SPOTLIGHT

Naturally gluten-free when made with certified gluten-free mustard and arrowroot.
Vegan-friendly — contains no dairy, eggs, or animal products.
No artificial preservatives — store in the fridge and enjoy fresh flavour for weeks.

Note: This homemade version is rich in flavour with a sweet-tangy balance, perfect for sandwiches, wraps, and salads without the additives of store-bought sauces.

Nutritional Facts

Calories:	56.5
Sugar:	12.7
Sodium:	276.1
Fat:	0.3
Carbohydrates:	13.6
Fiber:	0.2
Protein:	0.2

Subway sweet onion sauce recipe

Servings 16 portions

Calories 56.5

Prep Time 5

Cook Time 10

Total Time 15

Fat: 0.3|Carbohydrates: 13.6|Protein: 0.2

Pin Recipe

Description

Missing Subway’s sweet onion sauce? Make it at home in 15 mins—lasts forever! Perfect for sandwiches. Easy, tasty copycat recipe.

Ingredients

½ cup (120ml) cold water
6 tbsp white vinegar
2 tbsp red wine vinegar
1 drop sesame oil up to 2 drops
2½ tsp Dijon mustard
¾ tsp fresh onion juice use a garlic press
1 cup (200g) granulated sugar
1 tbsp arrowroot
1 tbsp minced onion flakes
2½ tsp mustard powder
½ tsp celery seed
1 tsp poppy seed
1 tsp salt
¼ tsp garlic salt plus 1/8 teaspoon
¼ tsp paprika plus 1/8 teaspoon
¼ tsp black pepper

Instructions

Combine the ingredients by whisking them all together.
Bring the mix to boil in a small saucepan over medium-high heat, Whisk frequently to avoid burning.
Lower the heat and simmer whisking until the mixture thickens.
Let it cool and place in the fridge consuming it within one month; or freeze.

Recipe Notes:

Storage: Keeps 1 month refrigerated or 3+ months frozen (thaw before use).
Thickener Swap: Arrowroot = cornstarch (1:1).
Vinegar: All white vinegar works if no red wine vinegar.
Onion Juice: Grate onion & squeeze pulp for juice (or use ½ tsp onion powder in a pinch).
Sesame Oil: Optional—adds subtle depth, but can be skipped.
Spices: Celery/poppy seeds add texture but aren’t essential.
Adjust Sweetness/Tang: Add more sugar or vinegar to taste.
Texture: For a smoother sauce, blend after it has cooled.
Servings: You will get 1 cup of sauce, making 16 servings (1 tablespoon each).