Why You’ll Love This Recipe

If you’re a fan of the signature sweet and tangy sauce from Subway sandwiches, this homemade Subway Sweet Onion Sauce recipe will bring that same delicious flavor to your kitchen! The perfect balance of sweet sugar, zesty vinegar, and a hint of onion, this sauce is the ideal topping for sandwiches, wraps, salads, and more. With just a few simple ingredients, you can recreate this fan-favorite sauce at home and elevate any meal. Whether you’re making your own subs or just adding a little extra flavor to a salad, this sauce is a must-have for any sauce lover!

Ingredients

• 1 cup sugar
• ½ cup water
• 6 tablespoons white vinegar
• 1 ½ tablespoons red wine vinegar
• ½ tablespoon finely minced onion
• 1 tablespoon cornstarch
• 2 teaspoons Dijon mustard

Tip: You'll find the full list of ingredients and measurements in the recipe card below.

Directions

1. In a small saucepan, combine the sugar, water, white vinegar, and red wine vinegar. Stir the mixture over medium heat until the sugar completely dissolves.
2. Add the finely minced onion and bring the mixture to a simmer. Let it cook for about 5 minutes, allowing the onion to soften and infuse the sauce with flavor.
3. In a separate small bowl, mix the cornstarch with a little cold water to create a slurry.
4. Slowly pour the cornstarch mixture into the saucepan while stirring. Continue to cook the sauce for 2-3 minutes, until it thickens.
5. Remove the saucepan from the heat and stir in the Dijon mustard, ensuring it’s fully incorporated into the sauce.
6. Let the sauce cool to room temperature. Once cooled, transfer the sauce to a bottle or jar for easy storage.
7. Use immediately or store in the refrigerator for up to 2 weeks.

Servings and Timing

• Servings: Approximately 1 ½ cups of sauce
• Prep Time: 5 minutes
• Cook Time: 10 minutes
• Total Time: 15 minutes

Variations

• Spicy Version: Add a pinch of cayenne pepper or a splash of hot sauce to give the sweet onion sauce an extra kick.
• Garlic Infused: Add a clove of minced garlic while simmering the sauce to add depth of flavor.
• Honey Sweetened: Replace the sugar with honey for a more natural sweetener and a subtle floral taste.
• Vegan: To make the sauce vegan, simply substitute the Dijon mustard with a vegan-friendly variety.

Storage/Reheating

• Storage: Store the sweet onion sauce in an airtight container or bottle in the refrigerator. It will stay fresh for up to 2 weeks.
• Reheating: If you prefer a warm sauce, simply heat it gently on the stovetop over low heat, stirring occasionally until warmed through.

FAQs

1. Can I use apple cider vinegar instead of white vinegar?

Yes, you can substitute apple cider vinegar for white vinegar. It will give the sauce a slightly different flavor, but still delicious!

2. How can I make this sauce thicker?

If you’d like a thicker sauce, increase the cornstarch slightly or let the sauce simmer for a bit longer to reduce and thicken naturally.

3. Can I make this sauce spicier?

Yes, you can add a pinch of cayenne pepper or a few drops of hot sauce to add some heat to the sauce.

4. How long will this sauce last in the fridge?

This sauce can be stored in an airtight container in the fridge for up to 2 weeks. Just be sure to give it a good stir before using.

5. Can I freeze this sauce?

It’s not recommended to freeze this sauce as the texture may change once thawed. It’s best to make it fresh and store it in the fridge.

6. Is this sauce gluten-free?

Yes, this recipe is naturally gluten-free, but always check the labels on ingredients like Dijon mustard to be sure there are no hidden gluten-containing additives.

7. Can I use red onion instead of regular onion?

You can use red onion, but keep in mind that it has a milder, slightly sweeter flavor compared to regular white onion.

8. Can I make this sauce without cornstarch?

Cornstarch is essential for thickening the sauce. However, you can use arrowroot powder or potato starch as an alternative thickening agent.

9. Can I make this sauce without vinegar?

If you're looking to make a non-vinegar version, try using lemon juice as a substitute for the tangy element, though the flavor will differ slightly.

10. Can I use this sauce for other dishes?

Absolutely! This sauce works great as a dressing for salads, a dip for vegetables, or even a topping for grilled meats or roasted veggies.

Conclusion

Making your own Subway Sweet Onion Sauce at home is simple and rewarding. With its perfect balance of sweet, tangy, and savory flavors, this sauce is ideal for enhancing your sandwiches, wraps, or any dish that could use a flavorful kick. Whether you're enjoying it on a homemade sub or using it as a salad dressing, this sauce is sure to become a staple in your kitchen. Whip it up in just a few minutes and enjoy the taste of Subway in the comfort of your own home!

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Subway Sweet Onion Sauce

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• Author: Ava
• Total Time: 15 minutes
• Yield: 10-12 Servings
• Diet: Gluten Free

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Description

Recreate the signature Subway Sweet Onion Sauce right at home! With a perfect balance of sweet, tangy, and savory flavors, this homemade sauce is perfect for sandwiches, wraps, salads, and more. Featuring a blend of sugar, vinegars, Dijon mustard, and a hint of onion, it’s a simple yet delicious topping that will elevate your meals. Ready in just 15 minutes, this sauce is a must-have for any fan of the popular Subway sandwich!

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Ingredients

• 1 cup sugar
• ½ cup water
• 6 tablespoons white vinegar
• 1 ½ tablespoons red wine vinegar
• ½ tablespoon finely minced onion
• 1 tablespoon cornstarch
• 2 teaspoons Dijon mustard

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Instructions

1. In a small saucepan, combine the sugar, water, white vinegar, and red wine vinegar. Stir over medium heat until the sugar dissolves completely.
2. Add the finely minced onion and bring the mixture to a simmer. Cook for about 5 minutes to soften the onion and infuse the sauce.
3. In a small bowl, create a slurry by mixing the cornstarch with a bit of cold water.
4. Slowly pour the cornstarch mixture into the saucepan while stirring. Cook for 2-3 minutes until the sauce thickens.
5. Remove from heat and stir in the Dijon mustard until fully combined.
6. Let the sauce cool to room temperature before transferring it to a bottle or jar for easy storage.
7. Use immediately or refrigerate for up to 2 weeks.

Notes

• For extra spice, add a pinch of cayenne pepper or a splash of hot sauce to the sauce.
• Garlic lovers can add minced garlic while simmering the sauce.
• Honey sweetened: Replace sugar with honey for a more natural sweetness.
• To make this sauce vegan, swap the Dijon mustard with a vegan-friendly variety.

• Prep Time: 5 minutes
• Cook Time: 10 minutes
• Category: Snack
• Method: Stovetop
• Cuisine: American