Yes, first defrost them. Leave them in the frig over night and it should defrost.
Just remember this, there is going to be alot of water after you cook the flounder so make sure you cook it in some sort of pan that has a raised edge or use foil and turn up the ends so that the water doesn't drip all over your oven.
You can put what ever spice you like on it, I use sea food seasoning or Old Bay seasoning, some people like to squeeze lemon on it as well. Just put the fish (grayish side down) and sprinkle w/seasoning and bake at a high temperature 400 degrees for about 10 minutes. They cook very fast so depending on the thickness you need to watch it. It shoud be white and flakey when done, not that white/clear icky raw color. Serve up w/some low cal tarter sauce.
You can do this on the grill as well but make a foil boat. If you put the fish directly on the grill w/out the foil it will stick and break and be very hard to turn.
To me this is the easiest, low cal way to make it.
If you like Flounder, you'll love Tilapia fish (sp?) and orange roughy MMMMM!!!!
Hope this helps.
~ WORRY LOOKS AROUND, SORRY LOOKS BACK, FAITH LOOKS UP ~
Courage doesn't always roar.
Sometimes courage is the quiet voice at the end of the day saying,
"I will try again tomorrow."