Heat a large nonstick skillet over medium heat. Add garlic cloves to pan; cover and cook 8 minutes or until lightly browned and tender when pierced with a fork, stirring occasionally. Cool slightly. Squeeze garlic from skins into the bowl of a mini food processor. Discard skins. Puree garlic until smooth.
Combine yogurt, sour cream, chives, salt, and pepper in a medium bowl, stirring well with a whisk. Add garlic to yogurt mixture, stirring with a whisk to combine.
I really loved the grill-roasted garlic but after adding in the rest of the ingredients, it just sort of lost the flavor impact. It also comes out a somewhat unpleasant color. Doubt I'd make it again. There are definitely better dips out there.