Prepare the Filling: In a medium bowl, mix together the grated zucchini, shredded cheddar, softened cream cheese, minced garlic, and salt. Mix thoroughly until everything is evenly incorporated, then set it aside.

Prepare the Chicken: Preheat the oven to 375°F (190°C). Pat the chicken breasts dry and make a deep pocket in the side of each breast, being careful not to cut through to the other side.

Season the Chicken: In a small bowl, mix the garlic powder, onion powder, paprika, cayenne pepper, and kosher salt. Evenly distribute the seasoning blend across both sides of the chicken breasts, ensuring full coverage.

Stuff the Chicken: Divide the zucchini-cheese filling evenly and stuff each chicken breast pocket with the mixture. Secure the edges with toothpicks to keep the filling inside while cooking.

Cook the Chicken: Heat an oven-safe skillet over medium heat and spray lightly with olive oil. Sauté the stuffed chicken breasts for 2 to 3 minutes per side until they achieve a golden-brown crust.

Bake: Transfer the skillet to the preheated oven and bake for 15-20 minutes, or until the chicken is fully cooked and the internal temperature reaches 165°F (74°C). Remove the toothpicks before serving.

Serve: Serve hot with a side of vegetables or a fresh salad for a complete meal.