Slice eggs in half lengthwise; remove yolks and reserve 4 whole yolks for another use.
Combine yogurt and next 6 ingredients (through hot pepper sauce) in a medium bowl; mash with a fork. Add remaining yolks; beat with a mixer at high speed until smooth. Spoon about 1 tablespoon yolk mixture into each egg-white half. Cover and chill 1 hour. Garnish with green onions, if desired.
Note: To perfectly center the yolks before hard-boiling the eggs, wrap a rubber band around your egg carton and refrigerate the carton on its side for several hours or overnight.