This recipe makes a basic sauce to bake fish. The purpose of the sauce is to keep the fish from sticking to the baking pan and to add some flavor without masking the natural flavor of the fish. Although you can mask the flavor of the fish if you wanted to, by just doubling the sauce ingredients.

I used Tilapia, for the fish, which seems to be the only kind I can get where I live. I get 4-5 pieces per package. This recipe works for 2 pieces. Most of the time, I don't measure, so the only critical part to this is making sure the fish is cooked. How much of anything you put in, is subject to your taste.

Preheat oven to 350 degrees.
While the oven is heating...
Cut up mushrooms - the kind that come from the produce section as opposed to canned. I usually grab two hands-full which I guess is about 5-6.
Cut up one half a white onion - wedge sliced or left in rings
Optional cut up one apple. In the picture I used a Granny Smith.

In a large sauce pan on medium heat put...
One tablespoon honey
One tablespoon tamari OR one pinch sea salt
One tablespoon olive oil OR one tablespoon butter. If your diet can afford the use of butter, this works a little better flavor wise than the olive oil for me, mostly because I have to special order decent olive oil and I usually don't take the trouble to do so.
Heat until everything mixes together easily.

Take a spoon or whatever you use for this kind of thing and lightly coat the fish on both sides. Place the fish in a baking dish. I used a Pyrex thingy for this.

When the oven is done preheating, put in the fish for 12-15 minutes. You cook each side for 12-15 minutes.

After you put the fish in for the first side, take the cut up mushrooms, onions and apple and put them in the saucepan with any remaining sauce. Heat at medium heat. You don't have to do much with these, they give off liquid as they cook so they just need an occasional stir.

When the fish is done on both sides, serve it smothered with mushrooms, onions and the apples if you've added them. I usually serve with bread, either a baked garlic loaf or a focaccia. The picture has the focaccia, with the thyme and olive oil on top, but not showing.

What makes this ancient? Its a stretch, but I'm pretty sure that onion, mushrooms, apples and fish have been around for awhile.
If you like fish, this is really easy to make. I don't have a lot of patience for cooking, but I can handle the prep work which never exceeds the pre-heat time of the oven here. It's easy clean up too. The hardest part is waiting for each side of the fish to cook, but a good book helps with that.
Best of all, the fish tastes good. There's something about the basic combination of sweet and salt plus however one characterizes the onion, but it balances those flavors in a good way.