How many servings does this recipe make?

This recipe makes 4 servings. You can adjust the portion size directly on this page.

What ingredients do I need for Onion-Smothered Roast Beef & Swiss Sandwich?

You need 7 ingredients. The key ingredients include: 1 tablespoon Hellmann's or Best Foods Dijonnaise Creamy Dijon Mustard, 2 slices whole grain bread seeded, 2 slices deli roast beef about 2 oz., 1/4 cup caramelized onion, and more.

Is Onion-Smothered Roast Beef & Swiss Sandwich suitable as meat & poultry?

Yes, Onion-Smothered Roast Beef & Swiss Sandwich falls under the Meat & Poultry category and is a great choice for this type of meal.

How do I store leftover Onion-Smothered Roast Beef & Swiss Sandwich?

Store leftovers in an airtight container in the refrigerator for up to 3–4 days. Reheat gently before serving.

Onion-Smothered Roast Beef & Swiss Sandwich Recipe

Name: Onion-Smothered Roast Beef & Swiss Sandwich
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 4 servings
Ingredients: 1 tablespoon Hellmann's or Best Foods Dijonnaise Creamy Dijon Mustard; 2 slices whole grain bread seeded; 2 slices deli roast beef about 2 oz.; 1/4 cup caramelized onion; 2 ounces brie cheese; 2 lettuce leaves green curly leaf; 2 slices tomato optional

Try this homemade Onion-Smothered Roast Beef & Swiss Sandwich recipe the whole family will love. Made with Dijonnaise, bread, deli and caramelized onion…

This Onion-Smothered Roast Beef & Swiss Sandwich relies on simple, everyday ingredients such as whole grain bread seeded, deli roast beef about 2 oz., caramelized onion and brie cheese. It comes together quickly and makes 4 servings, at about 113 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.

It's versatile enough for an easy weeknight dinner yet satisfying enough for guests at the weekend. Serve it with your favorite sides, and keep any leftovers for a quick meal the next day.

Updated Jun 30, 2026

Serves 4 Meat & Poultry

Servings: persons

1 tablespoon Hellmann's or Best Foods Dijonnaise Creamy Dijon Mustard
2 slices whole grain bread seeded
2 slices deli roast beef about 2 oz.
1/4 cup caramelized onion
2 ounces brie cheese
2 lettuce leaves green curly leaf
2 slices tomato optional

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Quick Info

Servings
4 servings
Calories
113 kcal
Category
Meat & Poultry

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Onion-Smothered Roast Beef & Swiss Sandwich

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