Homemade Sweet Onion Sauce
Recreate Subway’s famous sweet onion sauce with this easy copycat recipe. This Homemade Sweet Onion Sauce perfectly blends sweet and tangy flavors, making it a delightful addition to sandwiches, salads, and more. Whether for a casual lunch or an elegant dinner gathering, this sauce elevates any dish with its unique taste and versatility.
Why You’ll Love This Recipe
- Quick to Make: With just 15 minutes of your time, you can whip up a batch that lasts for days.
- Versatile Flavor: Perfect for sandwiches, salads, and as a dip; it complements many dishes.
- Easy Ingredients: Made from common pantry staples, there’s no need for special trips to the grocery store.
- Adjustable Sweetness: You can customize the sweetness to your liking by adjusting the sugar content.
- Vegan-Friendly: This sauce is entirely plant-based, making it suitable for various diets.
Tools and Preparation
Before diving into the recipe, gather your tools. Having everything ready makes the cooking process smoother and more enjoyable.
Essential Tools and Equipment
- Saucepan
- Whisk
- Airtight container
Importance of Each Tool
- Saucepan: Essential for cooking the sauce evenly without burning.
- Whisk: Helps combine ingredients thoroughly, ensuring a smooth texture.
- Airtight container: Keeps your sauce fresh in the refrigerator for up to one week.
Ingredients
To create this delicious Homemade Sweet Onion Sauce, you’ll need the following ingredients:
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 saucepan.
Step 2: Cook the Mixture
Bring to a boil while whisking constantly. Let it boil for 5 minutes. Reduce heat and let it simmer for another 5 minutes while continuing to whisk.
Step 3: Cool and Store
Remove from heat and allow the sauce to cool. Store in an airtight container in the refrigerator for up to one week.
Enjoy your Homemade Sweet Onion Sauce as a delightful addition to any meal!
How to Serve Homemade Sweet Onion Sauce
Homemade Sweet Onion Sauce is a versatile condiment that can elevate many dishes. Whether you’re hosting a barbecue or just enjoying a quiet dinner, this sauce adds a delightful sweetness and tanginess.
On Sandwiches
- Deli Delight: Spread it on turkey or ham sandwiches for a tasty twist.
- Veggie Wraps: Use it in wraps filled with fresh vegetables for added flavor.
As a Salad Dressing
- Green Salads: Drizzle over mixed greens for a sweet and tangy dressing.
- Coleslaw: Toss it with shredded cabbage for a creamy coleslaw alternative.
With Grilled Meats
- Grilled Chicken: Serve it alongside grilled chicken breast for an extra layer of flavor.
- Steak Dipping Sauce: Use as a dip for steak bites; the sweetness pairs well with savory meats.
In Marinades
- Marinate Vegetables: Coat veggies before grilling to enhance their natural flavors.
- Meat Marinade: Mix into marinades for pork or beef to create tender, flavorful dishes.

How to Perfect Homemade Sweet Onion Sauce
To achieve the best version of Homemade Sweet Onion Sauce, keep these tips in mind:
- Flavor Balancing: Adjust the vinegar levels based on your taste preference—more vinegar for tanginess, less for sweetness.
- Fresh Grated Onion: Use freshly grated onion instead of powdered for a fresher taste and texture.
- Whisk Constantly: While boiling, whisk continuously to avoid lumps from the cornstarch and ensure even consistency.
- Cool Gradually: Allow the sauce to cool completely before storing to maintain its quality and flavor.
Best Side Dishes for Homemade Sweet Onion Sauce
Homemade Sweet Onion Sauce pairs wonderfully with various side dishes. Here are some great options:
- French Fries: Crispy fries dipped in sweet onion sauce make for an irresistible snack.
- Onion Rings: Pair with onion rings for double the onion flavor in one delicious bite.
- Grilled Corn on the Cob: Brush corn with sweet onion sauce before grilling for a unique twist.
- Potato Wedges: Serve crispy potato wedges with this sauce as a dipping option.
- Roasted Vegetables: Drizzle over roasted carrots or bell peppers for added sweetness.
- Pita Chips: Enjoy with crunchy pita chips as an appetizer or light snack.
Common Mistakes to Avoid
Creating Homemade Sweet Onion Sauce can be simple, but there are some common errors to watch out for.
- Using the wrong vinegar: Always stick to white vinegar and red wine vinegar for the right balance of acidity and flavor.
- Overheating the sauce: Boiling for too long can affect the texture. Keep a close eye while cooking.
- Skipping ingredients: Each ingredient plays a role in achieving that perfect sweet and tangy flavor. Don’t omit any!
- Not storing correctly: Use an airtight container for storage to maintain freshness. Avoid using old jars that could introduce bacteria.
- Ignoring taste tests: Always taste your sauce during preparation. Adjust sweetness or tanginess according to your preference.

Storage & Reheating Instructions
Refrigerator Storage
- Store in an airtight container.
- Keep in the refrigerator for up to 1 week.
Freezing Homemade Sweet Onion Sauce
- Freeze in small portions for easy use later.
- Use freezer-safe containers or bags to prevent freezer burn.
- Best used within 3 months for optimal flavor.
Reheating Homemade Sweet Onion Sauce
- Oven: Preheat to 350°F (175°C). Place sauce in an oven-safe dish and heat until warm.
- Microwave: Heat in short intervals, stirring between each, until completely heated through.
- Stovetop: Warm over low heat, stirring frequently to prevent sticking.
Frequently Asked Questions
If you’re curious about making Homemade Sweet Onion Sauce, here are some common inquiries.
What is Homemade Sweet Onion Sauce?
Homemade Sweet Onion Sauce is a flavorful blend of sweet and tangy ingredients, perfect as a dressing or dipping sauce.
How can I customize my Homemade Sweet Onion Sauce?
You can adjust the sweetness by adding more sugar or experiment with different types of vinegars for unique flavors.
Can I make this sauce vegan?
Yes! All ingredients in this recipe are plant-based, making it a great vegan option for sandwiches and salads.
How long does Homemade Sweet Onion Sauce last?
When stored properly in the fridge, it lasts up to one week. For longer storage, consider freezing it.
Final Thoughts
This Homemade Sweet Onion Sauce is not only delicious but also incredibly versatile. It adds a delightful touch to sandwiches, salads, and more. Feel free to customize it according to your taste preferences; you might just create your new favorite condiment!

Homemade Sweet Onion Sauce
- Total Time: 15 minutes
- Yield: Approximately 12 servings 1x
Description
Recreate the beloved Subway experience at home with this easy Homemade Sweet Onion Sauce. This delightful condiment beautifully balances sweetness and tanginess, making it the perfect addition to sandwiches, salads, and more. With just a few common ingredients and a quick 15-minute preparation time, you can elevate any meal with this versatile sauce. Vegan-friendly and easily adjustable to suit your taste preferences, it’s a crowd-pleaser for casual lunches or elegant dinner parties alike. Get ready to enhance your culinary creations with this delicious homemade treat!
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 the mixture to a boil while whisking continuously for about 5 minutes.
- Reduce heat and let simmer for another 5 minutes while whisking until thickened.
- Remove from heat and allow the sauce to cool before transferring it to an airtight container for storage.
- Prep Time: 10 minutes
- Cook Time: 5 minutes
- Category: Condiment
- Method: Cooking
- Cuisine: American
Nutrition
- Serving Size: 30g
- Calories: 60
- Sugar: 13g
- Sodium: 80mg
- Fat: 0g
- Saturated Fat: 0g
- Unsaturated Fat: 0g
- Trans Fat: 0g
- Carbohydrates: 15g
- Fiber: 0g
- Protein: <1g
- Cholesterol: 0mg