In a mixing bowl, combine ground chicken, onion, garlic, salt, black pepper, smoked paprika, breadcrumbs, and egg. Mix well to create a cohesive mixture.

With damp hands, form the chicken mixture into 8 equal patties, each slightly larger than your slider buns (they will shrink as they cook).

Heat olive oil in a large skillet or grill pan over medium heat.

Cook chicken patties for 4-5 minutes per side, until golden brown and cooked through (internal temperature should reach 74°C/165°F).

In the last minute of cooking, place a half-slice of cheddar cheese on each patty to melt.

While patties are cooking, slice the slider buns and toast them lightly if desired.

Mix mayonnaise and mustard together, then spread a thin layer on each bun bottom.

Layer a lettuce leaf, chicken patty with melted cheese, tomato slice, and pickles (if using) onto the buns. Cover with bun tops.

Serve sliders immediately while warm.