Leftover Steak Sandwich with Onions and Mushrooms

Turn last night’s dinner into today’s gourmet lunch with this irresistible Leftover Steak Sandwich with Onions and Mushrooms. Perfectly repurposing your leftover steak, this recipe layers tender, thinly sliced beef with sweet caramelized onions, savory sautéed mushrooms, and melted provolone or cheddar cheese, all on a toasted sandwich roll. A creamy blend of mayonnaise and Dijon mustard adds a tangy finish, while a quick press on the skillet gives the sandwich a satisfying crunch. Ready in just 35 minutes, this hearty sandwich is a delicious way to reduce food waste and elevate simple ingredients into a bistro-worthy meal. Perfect for steak lovers and busy cooks craving bold flavors!

Nutriscore Rating: 66/100

Prep Time:15 mins

Cook Time:20 mins

Total Time:35 mins

Servings: 2

Ingredients

• 8 oz leftover steak
• 1 large onion
• 8 oz mushrooms
• 2 tbsp olive oil
• 1 tbsp butter
• 2 cloves garlic
• 0.5 tsp salt
• 0.5 tsp black pepper
• 2 sandwich rolls or buns
• 2 slices sliced provolone or cheddar cheese
• 2 tbsp mayonnaise
• 1 tbsp dijon mustard

Directions

Step 1

Thinly slice the leftover steak and set aside.

Step 2

Peel and thinly slice the onion. Clean and slice the mushrooms. Mince the garlic cloves.

Step 3

Heat 1 tablespoon of olive oil and the butter in a large skillet over medium heat.

Step 4

Add the sliced onions to the skillet. Sprinkle with a pinch of salt and cook for 8-10 minutes, stirring occasionally, until the onions are golden and caramelized. Transfer the onions to a plate and set aside.

Step 5

In the same skillet, add another tablespoon of olive oil. Add the sliced mushrooms and cook for 6-8 minutes until they are browned and softened. Add the minced garlic, salt, and black pepper, and cook for an additional 1-2 minutes. Transfer to the plate with the onions.

Step 6

Wipe the skillet clean and lightly toast the sandwich rolls or buns over medium heat. Remove and set aside.

Step 7

In the same skillet, warm the sliced leftover steak over medium-low heat for 1-2 minutes until just heated through.

Step 8

Spread 1 tablespoon of mayonnaise and 1/2 tablespoon of Dijon mustard on the bottom half of each sandwich roll.

Step 9

Layer the warmed steak slices, caramelized onions, sautéed mushrooms, and a slice of cheese onto the rolls.

Step 10

Place the top half of the roll on the sandwich and press gently.

Step 11

Optionally, return the sandwich to the skillet or grill pan over low heat, and press with a spatula for 1-2 minutes on each side to melt the cheese and slightly crisp the bread.

Step 12

Serve warm and enjoy your flavorful leftover steak sandwich!

Nutrition Facts

Serving size	(949.3g)

Amount per serving	% Daily Value*
Calories	2028.6

Total Fat 128.8g	0%
Saturated Fat 37.4g	0%
Polyunsaturated Fat 6.8g
Cholesterol 289.7mg	0%
Sodium 3334.9mg	0%
Total Carbohydrate 117.3g	0%
Dietary Fiber 8.0g	0%
Total Sugars 24.1g
Protein 96.0g	0%

Vitamin D 14.2IU	0%
Calcium 590.1mg	0%
Iron 11.5mg	0%
Potassium 2292.8mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 57.6%

Protein: 19.1%

Carbs: 23.3%