Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to blacken fish [title] Heat a dry cast iron pan over medium-high heat. [step] A cast iron pan is a required tool for blackening fish, as other pans aren't capable of delivering the intense heat needed for this preparation. Set the pan onto a charcoal grill or a propane burner set to medium-high heat.

Ending1: [substeps] Gently pop the bottom of a cast iron pan so it separates from the rest of the pan. You should now be able to separate the shell from the bone. Ending2: Allow the pan to heat for about 10 or 15 minutes, and do not add any oil to the pan. [title] Melt some butter in a shallow pan. Ending3: [substeps] Always do a close inspection of the cast iron pan before placing it on the grill. If it seems unsafe, set a wax pad directly over the pan to keep it cool. Ending4: Allow the pan to heat until it becomes hot, then remove it from the burner. [title] Stuff and sear the fish pieces on a 40 degree surface.

Answer format: ending1/ending2/ending3/ending4