Deviled Eggs with Pickled Onions

When steamed, the eggs are perfectly cooked and easy to clean. Hot pepper sauce easily replaces sriracha.
Pour water into a large saucepan to a depth of 1 inch; place a large vegetable steamer in the pan. Add the eggs to the steamer. Bring the water to a boil over medium-high heat. Steam the eggs under the lid for 16 minutes. Remove from heat. Put the eggs in a large bowl filled with ice water for 3 minutes.While the eggs are steaming, combine 1/4 cup water, vinegar, and sugar in a medium-sized bowl suitable for a microwave oven; reheat in the microwave on high power for 2 minutes or until boiling. Add the onion. Let stand at room temperature for 15 minutes. Drain the water.Combine yogurt, mayonnaise, mustard, sriracha, pepper and salt in a medium bowl, mixing well.Peel the eggs; discard the shells. Cut the eggs in half lengthwise. Add 6 egg yolks to the yogurt mixture; reserve the remaining egg yolks for another use. Mash with a fork until smooth. Add 2 tablespoons of red onion. Spoon the mixture over the egg white halves (about 1 tablespoon for each half). Garnish the egg halves with the remaining red onion and spring onions.