Cutting the potatoes into 1/2-inch pieces ensures that maximum surface area is exposed to soak up garlicky flavor.
•1. Place cut potatoes in colander. Rinse under cold running water until water runs clear. Drain thoroughly.
•2. Melt 4 tablespoons butter in Dutch oven over medium heat. Cook garlic and sugar, stirring often, until sticky and straw colored, 3 to 4 minutes. Add rinsed potatoes, 1 1/4 cups half-and-half, water, and 1 teaspoon salt to pot and stir to combine. Bring to boil, then reduce heat to low and simmer, covered and stirring occasionally, until potatoes are tender and most of the liquid is absorbed, 25 to 30 minutes.
•3. Off heat, add remaining butter to pot and mash with potato masher until smooth. Using rubber spatula, fold in remaining half-and-half until liquid is absorbed and potatoes are creamy. Season with salt and pepper. Serve.
Great Roasted Garlic Flavor
1. Cook the minced garlic (and a little sugar) in butter until the garlic is sticky and straw-colored; this blooms the garlic's sweet flavor and tempers its harshness.
2. For deeply integrated garlic flavor, toss the raw potatoes with the garlic-butter mixture, ad the half-and-half and water directly to the pot, cover, and gently cook until tender.