Slow-cooked Italian beef - chinese grandma

Ingredients

• 4 pound boneless beef roast (shoulder aka cross rib, chuck, or rump roast aka bottom round)
• 1 medium onion, chopped
• 1 jar peperoncini peppers (10 to 16 ounces, depending on if you want mild or spicy), juice reserved, stems removed
• 2 cloves garlic
• 4 beef bouillon cubes (or 4 teaspoons Better Than Bouillon beef soup base)
• 2 tablespoons Worcestershire sauce
• 1 tablespoon dried oregano
• 1 tablespoon dried basil
• 1 tablespoon dried thyme
• 3 drops hot pepper sauce, or to taste (optional)
• Salt and black pepper, to taste