Recipe

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This Philly Cheesesteak Grilled Cheese gives steak-night leftovers an encore or, it can be made quickly with deli roast beef! The way the ingredients melt together is going to rock your lunches world.

Keep reading to see how to pack this tasty sandwich in the lunchbox without missing crunchiness on the way.

Philly Grilled Cheese Sandwich Lunch in a lunchbox

Grilled Philly Sandwich

This Philly Cheesesteak Grilled Cheese tastes and looks gourmet because it's that good. It's a meal that both kids and adults will love. The veggies and steak layered between melted cheese… C'mon what's not to love? And it’s made with none other than leftovers!

You're probably always wondering what to do with that small serving of beef from steak night, fajitas, or a slow cooker stew, I know I am! Since you most likely have more than one person to feed, you've got to stretch those leftovers. With this sandwich, my friends, problem solved!

Of course, if leftover steak is unheard of in your home, this could also be made with deli-sliced roast beef. I promise it's a total upgrade from a regular sandwich.

What is in Philly Cheesesteak Grilled Cheese

Nothing more than delicious steak leftovers and classic sandwich staples is what you need to build an epic lunch that fills bellies and satisfies any craving! What I included on this grilled cheese is:

Thick bread: such as Italian or rustic bread.
Butter: for grilling
Onion and pepper mix: thawed it before sauteing it.
American cheese: or your favorite sliced cheese.
Steak: leftover grilled steak or deli-cut roast beef.

You'll find the measurements in the recipe card below.

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How to pack Philly Cheesesteak Grilled Cheese for School Lunch

How does one pack a grilled sandwich inside a lunchbox you ask? Simple! Follow these steps and everything will stay fresh and crispy. Here’s how I assemble the sandwich:

Prep the bread
Butter one side of each bread slice and set aside.
Sauté veggies and steak
Melt the butter on a griddle or skillet over medium-high heat. Add the onion and pepper mix, sauté for 3 to 4 minutes or until onions have softened. Add the leftover steak or roast beef onto the griddle or skillet and cook until warmed through. Remove from heat.
Grill it
Onto the griddle or skillet, place the bread slices butter side down and grill, until golden brown. Remove from heat and set aside.
Make the sandwiches
Once bread is ready, spread the onion and beef mixture on the griddle, separate into 2 sections and top with each section with 2 cheese slices. Once the cheese is melted, transfer each section onto a toasted bread slice, assemble the sandwiches. Serve immediately or pack it for lunch.
Pack it for lunch
To pack this grilled cheese inside a lunchbox, wait for the sandwich to cool down to room temperature. Once cool, slice it in half and pack it inside the lunchbox along with fruit, veggies, or your favorite sides.

Check out this easy and quick video with all the tips:

More pro tips for packing grilled sandwiches for lunch

Follow these tips for packing perfect sandwich lunches every time:

Allow it to cool down
If you pack this -or any- grilled sandwich immediately after grilling it, the steam will make the bread get soggy. Keep crunchiness intact by allowing the grilled cheese to cool down completely before placing it in the lunchbox.

Use a firm container
Pack this sandwich in a sturdy, sandwich-size container to keep the grilled cheese from falling apart in the lunch bag. Here are my go-to lunch containers.

Separate dry from wet ingredients
When packing this Philly Cheesesteak Grilled Cheese, you may want to add veggies, fruits, and other healthy sides for the ultimate balanced school lunch. Place the sandwich separated from wet ingredients, to keep the bread from getting soggy.

Add more nutrition
This sandwich has it all! But what about adding more veggies and fruits? Great idea! Carrots, snap peas, grapes, berries, banana chips… you get the idea. Anything that feels like snacking will be a kid-favorite. Healthy desserts and school snacks are also welcome!

Philly Cheesesteak Grilled Cheese in a school lunchbox

School Lunch Philly Cheesesteak Grilled Cheese

Servings: 1 sandwich

Prep Time: 2

Cook Time: 10

Total Time: 12

5 from 20 votes

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Ingredients

2 slices thick bread, such as Italian or rustic bread
½ tablespoon butter, for grilling
⅛ cup finely diced onion and pepper mix, thawed
2 slices American cheese
½ cup leftover grilled steak or 2 slices deli-cut roast beef

Instructions

Make the sandwich:

Butter one side of each bread slice and set aside.
Melt the butter on a griddle or skillet over medium-high heat. Add the onion and pepper mix, sauté for 3 to 4 minutes or until onions have softened. Add the leftover steak or roast beef onto the griddle or skillet and cook until warmed through. Remove from heat.
Onto the griddle or skillet, place the bread slices butter side down and grill, until golden brown. Remove from heat and set aside.
Once bread is ready, spread the onion and beef mixture on the griddle, and top it with 2 cheese slices.
Once the cheese is melted, transfer onto a toasted bread slice and assemble the sandwich. Serve immediately or pack it for lunch.

Pack it for lunch:

To pack inside a lunchbox, wait for the sandwich to cool down to room temperature.
Once cool, slice it in half and pack it inside the lunchbox along with fruit, veggies, or your favorite sides.