Let’s start by prepping our ingredients. Slice the onion and bell peppers thinly. If you’re adding any extra toppings like mushrooms or jalapeños, slice them up too.

Next, split the hoagie rolls lengthwise, making sure to keep one side intact to hold all the delicious filling. Have your provolone cheese slices ready to go for assembling the sandwiches.

Heat up a tablespoon of olive oil in a large skillet over medium heat. Add in the ground beef, breaking it apart with a spatula as it cooks.

Cook it until it’s nicely browned and no longer pink, which should take about 5-7 minutes. Once it’s done, transfer the beef to a plate and set it aside.

Using the same skillet, add another tablespoon of olive oil if needed. Toss in the sliced onions and bell peppers, and let them cook until they’re soft and slightly caramelized, which usually takes about 8-10 minutes. To taste, add salt and pepper to season them.

Now, let’s put our sandwiches together. Preheat your oven’s broiler and place the split hoagie rolls on a baking sheet, cut side up.

Divide the cooked ground beef evenly among the rolls, spreading it out evenly. Top each sandwich with the sautéed onions and bell peppers, and then layer on two slices of provolone cheese.

Pop the baking sheet under the broiler and let the sandwiches cook until the cheese is all melty and bubbly, usually about 2-3 minutes. Keep an eye on them so they don’t burn!