Mix ground chicken, onion, breadcrumbs, egg, garlic powder, paprika, salt, and pepper until just combined.
Divide the mixture into 8 portions and shape into thin slider patties.
Chill the patties for 10–15 minutes if the mixture is very soft.
Heat olive oil in a skillet over medium heat.
Cook the patties for 4–5 minutes on the first side without pressing them down.
Flip and cook another 4–5 minutes until golden and fully cooked.
Check that the thickest part reaches 165°F, then add cheddar during the final minute and cover to melt.
Toast the slider buns lightly and spread with mayonnaise or burger sauce.
Place the cheesy patties on the buns and add lettuce, tomato, or pickles.
Serve warm.