Sour Mash Mash

Name: Sour Mash Mash
Ingredients: 2 rutabagas, peeled and cut into 1-inch cubes; 2 turnips, peeled and cut into 1-inch cubes; Sea or kosher salt and pepper, to taste; 2 russet potatoes, peeled and cut into 1-inch cubes; 2 to 4 ounces butter; 4 to 8 ounces buttermilk; 1 to 2 ounces good bourbon, or more