Roast Beef and Cheddar Sandwiches Recipe

Tanya Schroeder | Lemons for Lulu

Roast Beef and Cheddar Sandwiches has deli roast beef that gets topped with sautéed mushrooms, caramelized onions, and a homemade...

Roast Beef and Cheddar Sandwiches Photo

This is not an ordinary roast beef sandwich recipe! This sandwich has deli roast beef that gets topped with sautéed mushrooms, caramelized onions, and a homemade cheese sauce!

I did something recently that I rarely do. I ate a sandwich with fake cheese. We have been traveling for a baseball tournament this past weekend. We were in a relatively remote part of Kentucky.

Our tournament was held in this multi-field baseball park that was impressive. However, when it came to food, there was nothing to be had. The concession stand had a measly selection, and what was worse, the price of their food increased as the day wore on. The closest meal to be had was the one nearby fast food restaurant. And that's where I had the fake cheese.

Roast Beef and Cheddar Sandwiches Picture

There is certainly a place for fake cheese. I cannot watch an MLB game without my nachos and cheese. But for the most part, I prefer to make my own, homemade cheese sauce. Homemade cheese sauce tastes amazing on baked potatoes or these cheese steak fries, and it tastes especially good on a roast beef sandwich!

This roast beef sandwich recipe is a little on the gourmet side. Deli roast beef is topped with sautéed mushrooms and sweet caramelized onions. I like to pile on the mushrooms and onions; of course your tastes might be different; adjust accordingly.

Roast Beef and Cheddar Sandwiches Image

Also, a note on the onions: Caramelized onions are incredibly easy to prepare. If you cook onions long enough, they naturally become golden in color and sweeten as they cook. You could add a splash of vinegar (red wine, cider or balsamic) if you want to counteract a little of the natural sweetness, or you could intensify the flavor and stir in a little brown sugar instead. Either way, you win.

The cheese sauce starts with a basic roux; which is butter, flour, and milk that is whisked until smooth. I added shredded cheddar cheese, but you could easily substitute your favorite cheese (I see pepper jack in my future). Whatever cheese you use, I hope you enjoy this sandwich!

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Roast Beef and Cheddar Sandwiches Recipe

    2 Servings


For the Mushrooms:
  • 1/2 teaspoon Olive Oil
  • 4 ounces Mushrooms
  • Salt and Pepper
For the Caramelized Onions:
  • 1 small Onion, Sliced
For the Homemade Cheese Sauce:
  • 1 tablespoon Butter
  • 1 tablespoon Flour
  • 3/4 cup Milk
  • 1/3 cup Shredded Cheddar Cheese
To Assemble the Sandwiches:
  • 4 slices Rye Bread, Toasted
  • 4 slices Deli Roast Beef


  1. Heat a large skillet over medium heat. Add 1/2 teaspoon olive oil the skillet along with the mushrooms. Cook mushrooms for 2-3 minutes or until they begin to soften; season with salt and pepper. Remove mushrooms and set aside.
  2. Add onion slices to the same skillet. Cook onions for 10-15 minutes, stir occasionally. You want the onions to turn caramel in color and be quite soft. When onions have caramelized, remove from heat.
  3. Prepare the cheese sauce by stirring together butter and flour in a small saucepan over medium heat. Slowly whisk in the milk until the mixture is smooth. Stir in cheese.
  4. To assemble the sandwich, place 2 slices of roast beef on two slices of toasted bread.
  5. Top beef with cheese.
  6. Divide the mushrooms and onions between the two sandwiches, top with remaining bread slices and serve.


Cooking Method:
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Related Recipes:
Sandwich Recipes, Beef Recipes, Cheese Recipes, Easy Recipes, Easy Dinner Recipes, Lunch Recipes, Sauteed Recipes, Mushroom Recipes
Recipe Yields:
2 sandwiches
Prep Time:
Cook Time:
Total Time:
Related Post:
Author: Tanya Schroeder
Recipe Yields: 2 sandwiches
Prep Time: 5 minutes
Cook Time: 15 minutes
Total Time: 20 minutes

Nutrition Facts

Serving Size 1 sandwich
Servings Per Recipe 2

Amount Per Serving
Calories from Fat 160
Calories 526

% Daily Value*
Total Fat 20g
  Saturated Fat 4g
Sodium 2001mg
Total Carbohydrate 43g
  Dietary Fiber 3g
  Sugars 8g
Protein 32g

* Percent Daily Value are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.
** Nutrition Facts are estimated based on ingredients and data provided by Fat Secret. Please consult a doctor if you have special dietary needs.
Tanya Schroeder

About Tanya

Tanya covers every kind of meal on Lemons for Lulu. As our Sandwiches fanatic, she's going to wow you with Sandwich greatness, proving there's more to it than just bread, cheese, and meat.

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