Prepare the cucumbers: Wash and dry the cucumbers. Slice into 1/2-inch rounds. If the seeds are very wet, gently dab the tops with a paper towel so the egg salad sticks well.
Mix the dressing: In a medium bowl, whisk together Greek yogurt, mayonnaise, Dijon, lemon juice, garlic powder, a pinch of salt, and a few grinds of black pepper until smooth.
Add the mix-ins: Stir in the celery, red onion, and fresh herbs.
Fold in the eggs: Add the chopped hard-boiled eggs and gently fold until everything is evenly coated.
Taste and adjust seasoning with more salt, pepper, or lemon if needed.
Assemble the bites: Lay cucumber rounds on a platter. Spoon about 1 heaping tablespoon of egg salad onto each round. You can also use a small cookie scoop or piping bag for a neat look.
Finish with a sprinkle: Dust with paprika or everything bagel seasoning if you like.
A few extra herb leaves on top look great too.
Serve right away: Enjoy immediately for the best crunch. If prepping ahead, keep the egg salad chilled and assemble just before serving.