Warning, this will clog up some arteries.
it is also a bit messy, but it's worth the time and mess
1 can evaporated milk (not sweetened condensed milk)
1 cup all purpose flour seasoned to taste
1 package panko bread crumbs
Depending on number of fillets,
3-4 eggs beaten to omelette consistency
2-3 sticks butter
Sizeable sheet of aluminum foil
Take the fillets and put them in the milk, transfer a few at a time to the flour mixture and coat liberally, from the flour into the eggs, from the egg to the bread crumbs and then onto a plate.
Sometimes the egg will "run" from the flour, I pat the area with the egg on my finger till it "takes"
I try to maintain a dry hand (flour/panko ) and a wet hand (milk/egg) otherwise the buildup on the fingers becomes untenable.
Take your sheet of foil and turn the edges up to make a "cookie sheet" place this on your BBQ, depending on the number of fillets and how large the "cookie sheet" add a stick or so of butter, once melted and beginning to bubble, add fillets, cook four minutes per side on low to medium low heat.
Your target is golden brown.
And no worries about burning the house down.