To the bottom of at least an 8 quart slow cooker, add in the chopped onion, carrots, and celery.
1 large yellow onion, 4 medium carrots, 4 medium celery stalks
Place the turkey breast on top of the vegetables.
9 pound bone-in turkey breast
In a small bowl, melt the butter and add the steakhouse seasoning, poultry seasoning, garlic salt, smoked paprika, and black pepper. Whisk together to combine.