In a skillet, heat 2 tablespoons of olive oil over medium heat. Add sliced onions, green and red bell peppers, and mushrooms. Sauté for 5-7 minutes until tender and fragrant.

Stir in 1/2 cup of BBQ sauce along with minced garlic, kosher salt, and black pepper. Cook for an additional 2-3 minutes.

In a large mixing bowl, combine 1 pound of ground beef, 1 egg, 1/4 cup of diced onion, 1/2 cup of Italian breadcrumbs, 1 tablespoon of Worcestershire sauce, kosher salt, and black pepper. Mix gently.

Divide the meat mixture into four equal portions and shape them into patties about ¾ inch thick. Make a small indentation in the center of each patty.

Preheat your grill to medium-high heat, about 400°F. Oil the grates lightly. Grill the patties for 5-6 minutes on each side.

In the last minute of cooking, place a slice of pepperjack cheese on each patty to melt.

Toast your hamburger buns on the grill for about 1 minute.

Assemble the burgers with patties on the bottom bun and BBQ-glazed veggies on top before closing with the top bun.