Swapping flank steak for a thicker cut like butterflied chuck can yield a tougher spiral that resists even heat penetration on the grill.
- Pound the flank steak uniformly to a quarter-inch thickness so the meat cooks at the same rate as the rolled mushroom filling.
- Freeze the rolled meat log for 30 minutes before slicing to keep the pinwheels from falling apart under the knife.
- Secure each slice with multiple toothpicks placed strategically near the outer seam to prevent unravelling when flipped.
- Keep the grill at a medium-hot temperature, cooking the rounds for 4 to 6 minutes per side until an internal thermometer reads 145 degrees Fahrenheit for medium-rare.
- Store assembled uncooked pinwheels in the freezer for up to one month if wrapped tightly in plastic and foil, though fresh prep maintains better texture.
Scaling this preparation for larger groups simply requires working in batches on the grill grate to avoid dropping the cooking temperature. Proper spacing ensures each pinwheel develops a proper sear rather than steaming in its own juices.