Slow Cooker French Dip Sandwiches

Ingredients (14)

• 1 large sweet onion,
• 2 tablespoons extra-virgin olive oil,
• 2 large garlic cloves,
• 1 teaspoon Italian seasoning
• 1/2 teaspoon ground black pepper
• 1/2 teaspoon kosher salt
• 2 1/2 to 3 pounds beef brisket or boneless beef bottom round roast
• 1 1/4 cups low-sodium beef broth
• 1/2 cup water
• 1 tablespoon Worcestershire sauce
• 1 medium red bell pepper
• 1 medium green bell pepper
• 6 thin slices cheese
• 6 regular-sized sandwich rolls,