Place the eggs in a single layer in a large saucepan and cover with cold water by about 1 inch. Bring to a gentle boil over medium-high heat, then cover, turn off the heat, and let sit for 10–12 minutes. When the time is up, transfer the eggs to an ice bath and chill for at least 10 minutes.

Gently crack each egg all over, then peel under cool running water, starting from the wider end where the air pocket is. Set the peeled eggs aside.

Use a sharp knife to slice each egg in half lengthwise. Carefully pop the yolks into a medium mixing bowl and arrange the egg white halves on a serving platter or parchment-lined baking sheet.

Using a fork or small potato masher, mash the yolks until as smooth as possible. The smoother the yolks, the silkier the filling will be. A few tiny lumps are fine.

To the mashed yolks, add the mayonnaise, 1 tablespoon Sriracha, Dijon mustard, 1 teaspoon vinegar, garlic powder, salt, black pepper, and sour cream or Greek yogurt (if using). Stir until fully combined and creamy. Taste and adjust: add more Sriracha for extra heat, more vinegar for tang, or more salt as needed.

If the filling is too thick or stiff, whisk in a teaspoon of water, extra vinegar, or a bit more mayonnaise at a time until smooth and pipeable. It should hold its shape without feeling chalky.

Spoon the Sriracha yolk mixture into each egg white half, or transfer the filling to a piping bag fitted with a star tip (or a zip-top bag with the corner snipped off) and pipe decorative swirls into the whites.

Sprinkle the tops with smoked or regular paprika. Garnish with finely chopped chives, green onions, or cilantro. Add a thin jalapeño slice to some or all of the eggs if you like extra heat.

Refrigerate the deviled eggs for at least 30 minutes before serving to let the flavors meld and to firm up the filling. Serve chilled.