Preheat oven to 425°F. Slice about 1/4-inch off the top of the garlic heads, throw the tops away, and place heads on a piece of foil. Drizzle olive oil over the top of the garlic heads and wrap them well in the foil. Bake until tender and golden, about 35-45 minutes. Remove from oven and let stand until cool enough to handle. Peel the skin away from the garlic cloves.
Add the garlic cloves to a small nonstick saucepan along with the fat-free half-and-half. Simmer the mixture over medium heat until cream is hot. Reduce heat, cover the pan and continue to simmer for a couple of more minutes. Turn the heat off and lift out the garlic cloves with a slotted spoon, place in a custard cup, and set aside. Leave the saucepan with half-and-half on the stove until needed.
Place quartered potatoes in a large stockpot, cover with cold salted water, and bring to a boil. Cook until very tender, about 12 minutes. Drain potato pieces in a colander.
Add hot, steaming, and drained potato pieces directly to a large mixing bowl and beat on low while you slowly pour in the fat-free half-and-half. Season with salt and pepper if desired and gently stir in the roasted garlic cloves. Serve!