For the Pickled Red Onion

1. Combine all the ingredients into a jar of your choosing, ensuring that the liquid covers the slices of onion. Shake to combine, and let sit in the fridge for at least a day and up to 3 weeks.

For the Deviled Eggs

1. In a large pot, bring the water to a boil and place the eggs into the water, making sure that the tops of the eggs aren't covered. Cook the eggs over high heat for 8 minutes.
2. Remove the eggs and dunk into a bowl of water filled with ice water. Let sit for a few minutes before attempting to peel.
3. Once the eggs are cool, peel the shell and cut the eggs in half, lengthwise, carefully removing the cooked yolk and placing into a medium-sized bowl.  
4. Once all of the eggs have been halved and their yolks have been removed, add you mayonnaise, dijon, sumac, and salt to the bowl. Mash together with a fork so that it's well incorporated.
5. Using a pastry filling bag or the back of your spoon, refill your eggs with the yolk mixture forming a nice mound on the top of the egg white.
6. Garnish with your pickled red onion, black sesame seeds, and a pinch of sumac before serving.

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