Ditka’s Italian Beef Sandwich

Ingredients

• 5 pounds rump roast with lots of marbling
• 1 head garlic plus 2 cloves minced and divided
• 1 tablespoon kosher salt plus 1 teaspoon divided
• 1 tablespoon freshly ground black pepper plus 1/2 teaspoon, divided
• 1 tablespoon dried oregano
• 1 sprig fresh oregano
• 1 tablespoon red pepper flakes
• 2 red bell peppers cut into large, long chunks
• 2 green bell peppers cut into large, long chunks
• 2 tablespoons olive oil
• 2 loaves Italian bread fresh
• 1 cup giardiniera jarred hot