Drained nonfat yogurt—rather than mayonnaise or sour cream—provides the creamy texture. Start making this dip a day ahead, and try it with apple or pear slices.
Set strainer over medium bowl; line with double layer of cheesecloth. Place yogurt in cloth-lined strainer. Cover with plastic wrap; chill overnight.
Discard liquid drained from yogurt. Transfer yogurt to processor. Add cheese and garlic; blend until smooth. Transfer dip to bowl. (Can be made 1 day ahead. Cover; chill.) Sprinkle with celery seeds.
