With basically the same ingredients samfaina usually gets tagged as Spanish ratatouille. But Catalonians would argue that their neighbors to the north are really just making French samfaina.
We can leave the wrangling to the nationalist gastronomes and just be happy it's the time of year when all of the produce used in making this summery dish are abundant and delicious.
From the kitchen
Bean Pot or Pressure Cooker
The other difference between samfaina and ratatouille is more finely cut vegetables. So chop an eggplant, a zucchini, a red onion, and some kind of not-very-hot pepper (green preferred, but not a green bell pepper unless that's all you can find) into roughly quarter inch pieces. Cut up a clove or two of garlic, too.
I learned about grating tomatoes in Spain, and the technique works in any dish that uses them. Cut the tomatoes in half (across their "equator" so the stem end is on one half). Most recipes, including Pinotxo's, tell you squeeze out the seeds, but the seeds and their surrounding "jelly" contain most of the umami-rich glutamates, so leave them in.
Use your palm to rub the cut tomatoes gently across the large holes of a box grater set over a bowl until all that's left is the peel.
Pour several glugs of olive oil into big skillet (or any wide oven proof dish), then add the chopped vegetables, grated tomatoes, and a handful of golden raisins. Mix everything together with a few pinches of salt and put it, uncovered, into a 300F oven.
Let it cook for at least a couple of hours, stirring occasionally. In the end you want a thick, jam-like sauce. While you can eat samfaina by itself, spread on grilled bread, under a piece of fish, or spooned it over chicken. My favorite way is to stir it into a bowl of garbanzos. It tastes like slow-cooked summer.