In a large Dutch oven over medium heat, cook diced bacon until crisp. Remove bacon with a slotted spoon and set aside, reserving the rendered fat in the pot.
Increase heat to medium-high. Add the sliced beef to the bacon fat. Sear quickly until browned, then remove beef and set aside.
Add the onion and green peppers to the pot. Sauté for 6 minutes until softened and slightly browned.
Add minced garlic and cook for 60 seconds until fragrant.
Deglaze the pot with beef broth and Worcestershire sauce, scraping the bottom to release the fond. Add salt and pepper.
Return the beef and bacon to the pot. Bring to a boil, then reduce heat to low and simmer for 10 minutes.
Preheat oven to 400°F. Butter the baguette slices and top with 1 cup of shredded provolone cheese. Bake for 5-7 minutes until the cheese is bubbly and golden.
Stir the heavy cream and the remaining 1 cup of provolone cheese into the soup. Stir continuously until the cheese is fully incorporated and the broth is creamy.
Ladle the soup into deep bowls and serve immediately with the cheesy toast slices.