Homemade Sweet Onion Sauce
Recreate Subway’s famous Homemade Sweet Onion Sauce with this easy copycat recipe. This delightful sauce is a perfect blend of sweet and tangy flavors, making it an ideal addition to sandwiches, salads, and more. Whether you’re hosting a gathering or simply enjoying a meal at home, this versatile sauce will elevate your dishes with its unique taste.

Why You’ll Love This Recipe
- Quick and Easy: This recipe requires minimal prep time and can be made in just 15 minutes.
- Deliciously Versatile: Use it as a sandwich sauce, salad dressing, or dip for vegetables.
- Homemade Goodness: Enjoy the freshness of homemade ingredients without any preservatives.
- Customizable Flavor: Adjust the sweetness or tanginess to suit your personal taste.
- Vegan-Friendly: This sauce is perfect for those following a plant-based diet.
Tools and Preparation
Before you start making your Homemade Sweet Onion Sauce, gather a few essential tools to make the process smoother.
Essential Tools and Equipment
- Sauce pan
- Whisk
- Airtight container
Importance of Each Tool
- Sauce pan: A good quality saucepan ensures even heat distribution for perfect sauce consistency.
- Whisk: A whisk helps achieve a smooth mixture while combining all ingredients effectively.
- Airtight container: Storing your sauce in an airtight container keeps it fresh for longer.
Ingredients
Recreate Subway’s famous sweet onion sauce with this easy copycat recipe. Perfect blend of sweet and tangy flavors.
For the Sauce
- 1 Cup Sugar
- 1/2 Cup Water
- 6 Tablespoons White Vinegar
- 1 1/2 Tablespoons Red Wine Vinegar
- 1/2 Tablespoon Onion, freshly grated
- 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
How to Make Homemade Sweet Onion Sauce
Step 1: Combine Ingredients
Add all ingredients to a sauce pan.
Step 2: Heat the Mixture
Bring to a boil while whisking constantly. Let it boil for 5 minutes, then reduce heat to simmer for another 5 minutes, whisking continuously.
Step 3: Cool and Store
Remove from heat and allow to cool. Store in an airtight container in the refrigerator for up to 1 week.
Enjoy your delicious Homemade Sweet Onion Sauce! It’s sure to become a staple in your kitchen.
How to Serve Homemade Sweet Onion Sauce
Homemade Sweet Onion Sauce is versatile and can elevate a variety of dishes. Whether you’re preparing sandwiches, salads, or grilled meats, this sauce adds a delightful sweet and tangy flavor.
On Sandwiches
- Classic Sub: Drizzle over your favorite sub sandwich for that signature Subway taste.
- Wraps: Use it as a spread in wraps filled with veggies and protein for a refreshing twist.
- Burgers: Add a layer on top of burgers to enhance the overall flavor.
In Salads
- Salad Dressing: Mix with greens, nuts, and fruits for a delicious salad dressing that complements fresh ingredients.
- Pasta Salad: Toss into pasta salad for added sweetness and depth of flavor.
With Grilled Meats
- Chicken Skewers: Brush on grilled chicken skewers for a sweet glaze that caramelizes beautifully.
- Pork Chops: Use as a marinade for pork chops before grilling to infuse them with flavor.
As a Dip
- Vegetable Platter: Serve alongside fresh veggies as a dipping sauce for an easy appetizer.
- Chicken Nuggets: Pair with crispy chicken nuggets for an irresistible combination.

How to Perfect Homemade Sweet Onion Sauce
To make the best Homemade Sweet Onion Sauce, follow these tips to enhance its flavor and texture.
- Use Fresh Ingredients: Always opt for fresh onions and high-quality vinegars to ensure the best taste.
- Adjust Sweetness: Customize the sugar amount based on your preference; you can reduce it for less sweetness.
- Whisk Constantly: Keep whisking while boiling to prevent lumps and create a smooth consistency.
- Experiment with Flavors: Feel free to add herbs or spices like dill or cilantro for unique twists on the classic recipe.
Best Side Dishes for Homemade Sweet Onion Sauce
Pairing sides with your Homemade Sweet Onion Sauce can create a complete meal experience. Here are some fantastic options:
- Crispy French Fries: The sauce makes a perfect dip for hot, crispy fries loaded with flavor.
- Coleslaw: A crunchy coleslaw balances the sweetness of the sauce beautifully.
- Grilled Vegetables: Serve alongside grilled veggies to add a sweet contrast to their smokiness.
- Cornbread Muffins: Enjoy cornbread muffins dipped in sauce for a delightful treat at any BBQ.
- Potato Wedges: Roasted potato wedges paired with this sauce make for an excellent snack or side dish.
- Cheesy Garlic Bread: Spread on warm garlic bread for an irresistible twist that complements any meal.
Common Mistakes to Avoid
When making your Homemade Sweet Onion Sauce, it’s easy to overlook some details that can affect the final flavor and texture. Here are some common mistakes to watch out for:
- Skipping the Whisking: Failing to whisk constantly can cause the sauce to clump. Always keep whisking while heating for a smooth consistency.
- Not Measuring Ingredients Accurately: Using too much or too little of any ingredient can throw off the balance of flavors. Invest in measuring cups and spoons for best results.
- Ignoring Cooling Time: Rushing the cooling process can result in a thinner sauce. Let it cool completely before storing for optimal thickness.
- Using Old Ingredients: Stale spices and old condiments can diminish flavor. Ensure all your ingredients are fresh for the best taste in your sauce.
- Overcooking the Sauce: Boiling for too long can change the flavor profile. Follow the cooking time closely to achieve that perfect blend of sweet and tangy.

Storage & Reheating Instructions
Refrigerator Storage
- Store in an airtight container.
- Lasts up to 1 week in the refrigerator.
Freezing Homemade Sweet Onion Sauce
- Use freezer-safe containers or bags.
- Can be frozen for up to 3 months.
Reheating Homemade Sweet Onion Sauce
- Oven: Preheat to 350°F (175°C) and heat in an oven-safe dish until warm.
- Microwave: Heat in short intervals, stirring in between, until warmed through.
- Stovetop: Warm gently over low heat, stirring continuously to avoid burning.
Frequently Asked Questions
Here are some commonly asked questions about Homemade Sweet Onion Sauce:
Can I adjust the sweetness of my sauce?
Yes! You can increase or decrease the sugar based on your preference. Just remember that this will alter the overall flavor.
What dishes pair well with Homemade Sweet Onion Sauce?
This sauce is fantastic on sandwiches, salads, and as a dip for veggies or chips.
Is this sauce vegan-friendly?
Absolutely! All ingredients used in this recipe are plant-based, making it a perfect vegan option.
How do I make my sauce thicker?
If you prefer a thicker sauce, you can add more cornstarch mixed with water during cooking until you reach your desired consistency.
Final Thoughts
This Homemade Sweet Onion Sauce is not only easy to prepare but also versatile enough to enhance many dishes. Whether drizzled on salads or used as a spread on sandwiches, its sweet and tangy notes will surely delight. Feel free to customize it further by adding your favorite herbs or spices!

Homemade Sweet Onion Sauce
- Total Time: 15 minutes
- Yield: Approximately 10 servings 1x
Description
Indulge in the delightful flavors of Homemade Sweet Onion Sauce, a perfect blend of sweetness and tanginess that elevates any dish. This easy copycat recipe mirrors Subway’s iconic sauce, making it an ideal addition to sandwiches, salads, and more.
Ingredients
- 1 Cup Sugar
- 1/2 Cup Water
- 6 Tablespoons White Vinegar
- 1 1/2 Tablespoons Red Wine Vinegar
- 1/2 Tablespoon Freshly Grated 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 all ingredients in a saucepan.
- Bring to a boil, whisking constantly for about 5 minutes.
- Reduce heat and simmer for an additional 5 minutes while whisking.
- Remove from heat and let cool before storing in an airtight container in the refrigerator.
- Prep Time: 10 minutes
- Cook Time: 5 minutes
- Category: Condiment
- Method: Sauce preparation
- Cuisine: American
Nutrition
- Serving Size: 30g
- Calories: 70
- Sugar: 15g
- Sodium: 30mg
- Fat: 0g
- Saturated Fat: 0g
- Unsaturated Fat: 0g
- Trans Fat: 0g
- Carbohydrates: 17g
- Fiber: 0g
- Protein: <1g
- Cholesterol: 0mg