Prepare the Steak: Start by butterflying the flank steak to create a flat, even surface. Season both sides generously with kosher salt and black pepper.

Layer Filling: Lay the provolone cheese slices evenly across the butterflied flank steak, followed by adding fresh spinach on top.

Roll and Secure: Begin rolling the steak tightly from one end. Use wooden skewers to secure the roll every 1 to 2 inches.

Prep for Grilling: Brush the exterior with olive oil and season with salt and pepper. Cut into rounds between the skewers.

Grill: Preheat your grill to medium-high heat. Cook the pinwheels for approximately 4 minutes per side until the desired doneness.

Rest: Remove pinwheels from the grill and let them rest for about 5 minutes before slicing and serving.