Fish is easily overcooked, which makes it a strong candidate for slow cooking and an easy night's work for the cook--unless of course you complicate matters by throwing something tricky into the mix. I love a culinary dare. Rich fish like salmon and mackerel are delicious served with beans, but the two cook at such different rates, they typically can't be cooked together. By using red lentils, which are the softest of dried beans, and a forgiving fatty fish, like farm-raised salmon, I found I could trim the difference to about 10 minutes. A brief simmering of the lentils on their own does it; then the salmon is added and everything slow-bakes together in a low oven.
I like to use sockeye salmon for this dish -- its firm flesh and rich flavors are perfect for steaming