Push the vegetables to the side of the pan and add the ground beef. Use a spatula to crumble and brown the beef thoroughly. This should take around 8-10 minutes.
Season the mixture with salt and pepper to taste. Stir to combine the beef and vegetables evenly.
Reduce heat to low and sprinkle shredded cheese over the beef mixture. Cover the pan until the cheese melts, about 3-4 minutes.
Warm hoagie rolls in an oven or on a stovetop, fill with the cheesy beef mixture, and serve hot.
Notes
Store leftovers in an airtight container in the fridge for up to 3 days. Reheat in a skillet for best results.