Sauté garlic in hot oil in a Dutch oven over medium heat 3 minutes. Add 8 cups water, chicken broth, potatoes, and 1/4 tsp. salt; bring to a boil. Cover, reduce heat, and cook 15 to 20 minutes or until potatoes are tender.
Drain potatoes, and return to Dutch oven. Add buttermilk, butter, pepper, and remaining 1 tsp. salt. Mash potatoes with a large fork or potato masher to desired consistency. Sprinkle evenly with chives; serve immediately.
