Submerge the chicken fillets in pickle juice and refrigerate for 1 hour to brine.
Combine flour, powdered sugar, and smoked paprika in a shallow dish.
Remove chicken from brine, press each fillet into the flour mixture to coat both sides, then rest for 5 minutes.
Heat peanut oil in a large skillet over medium-high heat to 350°F / 175°C, then fry each fillet for 5 to 6 minutes per side until golden and cooked to 165°F / 74°C.
Place each fried fillet on a toasted brioche bun bottom, top with 4 pickle chips, then close with the bun top.