I find if I have,say, 6 flounders (two people fishing) in the cooler box, when they get home they all smell like iodine, even though they are on ice. The "iodine' smell is enough to make you chuck your biscuits.....
There is a way to fillet them so you get just fillets....(there is video on Youtube how to do it)....but my wife usually opts for the normal method of dressing them.
Flounders and Sole are big on the menu in Europe....not as much here.
I don't like the smell or the taste myself....
best depths to catch them for me are:- 50 to 120 ft over a sandy or muddy bottom or sand/gravel.
I use the smallest jig I can get away with that will still make it down there to the bottom without the current messing it up.
Just lower it down till it hits the sand and instead of yanking it up 4ft fast every 5 seconds......simply keep it down right near the sand and make it do the Aztec two-step for awhile/pause/ and then do it again.
Don't go very big on the hook...because they don't have that big a mouth.
I don't bother with baiting the hook....not necessary.....and I've caught hundreds of flounders this way.
Smearing an attractant like Smelly jelly or something similar on the jig works wonders.....
I often use herring oil......but you have to re-apply frequently.....
Flounders it seems aren't too fussy about the color of the jig much.....as opposed to some other bottom dwellers....