For easier shucking, steam clams over simmering water for two minutes or just until their shells barely open. Run a knife or small screwdriver around a shell's edge, and pop it open. If you partially steam the clams, reduce the broiling time by a minute or two. The clams may be unsteady on the jelly-roll pan, so you can line the pan with a bed of rock salt for more stability.
Worth the effort! I'd never shucked clams before and though time-consuming, it wasn't that bad - I even found a video on line that showed how to do it. These were the hit of the party and very unlike most of the spread. Because the clams are so small, I'd recommend the pancetta be sliced at 1/8 inch thickness or less. I used a bit of stuffing mix since we don't keep white bread in the house - it worked fine, and while it is "filler" you definitely need it to hold the ingredients together in the clam.
These were good but very time consuming. I choose to shuck the clams from raw... I do not recommend this method! I used whole wheat panko breadcrumbs in place of day old bread, but would probably cut back a little as it seemed like a look of filler. I would make this again and I would serve it to company. Next time I would steam clams to open though!
