I cook tuna steaks and salmon fillets on my GF grill and they come out perfect every time.
I put a little olive oil and seasoning on them first. They cook so fast, it's easy to overcook them, so you have to check for doneness after just a couple of minutes and keep a close eye on them.
Oh, and I've also cooked boneless pork chops on my GF grill. Same result - they come out great.
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