sweet and savory slow cooker pulled pork

Ingredients

• 1 (4.5 pound) bone-in pork shoulder roast
• 1 cup root beer
• 2 1/2 tablespoons light brown sugar
• 2 teaspoons kosher salt 1/2 teaspoon ground black pepper
• 1 1/2 teaspoons ground paprika 1/2 teaspoon dry mustard
• 1/2 teaspoon onion powder 1/4 teaspoon garlic salt
• 1/4 teaspoon celery salt
• 1/4 teaspoon ground cinnamon 1/4 teaspoon ground ginger 1/4 teaspoon ground nutmeg
• 1/3 cup balsamic vinegar 1 1/2 cups root beer
• 1 1/2 fluid ounces whiskey 1/4 cup brown sugar
• 1 tablespoon olive oil
• 3/4 cup prepared barbecue sauce 10 hamburger buns, split