The flavors here are sort of like ratatouille, but minus the eggplant.
However, the final consistency of the vegetables surrounding the fish is
more like a sauce because the vegetables are just about melted down by
the pot’s pressure in the two-step cooking process. If you find the sauce is
too thin after cooking, remove the fish from the pot and boil the sauce
down with the SAUTÉ function on MEDIUM, NORMAL, or CUSTOM 300°F for a
few minutes. Even so, we find that a little bit of, well, wateriness in the
sauce brings a lightness to the overall dish.
One note: It may seem strange, particularly in an 8-quart cooker, that
there’s no additional liquid with the tomatoes and other vegetables. The
zucchini will throw off so much liquid that the pot will come to pressure
without any burn notice. Just remember to use only diced tomatoes packed
in juice.