Mediterranean Zucchini Gratin

Heat 2 teaspoons of the oil in a wide skillet (with a lid) over medium high. Once hot, add sliced onions and thyme and stir for a few minutes, until softened but not browned. Reduce heat to medium, cover, and cook until very soft and fragrant, stirring occasionally, about 10 to 12 minutes. Adjust heat as needed so the onions sizzle gently. Remove from heat, season with a sprinkle of salt and pepper (about ¼ teaspoon each, or more to taste), and spread in the bottom of a standard sized gratin dish or pie plate.

Preheat oven to 375 F. Heat another teaspoon of oil in the same skillet over medium. When hot, add half the zucchini slices in close to a single layer. Cook, stirring every couple minutes, until starting to brown, about 5 to 7 minutes. If zucchini slices stick to the pan, reduce heat slightly. Off heat, season with salt and pepper to taste (as if you were eating them alone), then layer over the onions in the baking dish. Repeat cooking process with another teaspoon of oil and remaining zucchini, leaving the second half in the pan until needed.

Over the zucchini in the baking dish, layer half the basil, half the olives, and almost half of the Parmesan. Arrange all the mozzarella slices over the top, then repeat with another layer of zucchini, basil, olives, and Parmesan, leaving a tablespoon or so of Parmesan for later.

Cover baking dish with foil and bake 30 minutes. Remove from oven, uncover it and carefully sprinkle with pine nuts, the remaining 2 teaspoons olive oil and the remaining Parmesan. Bake for 10 minutes, until pine nuts are lightly browned. If not browned, heat under the broiler for a couple minutes, watching almost constantly so the pine nuts don’t burn.

I found it easiest to scoop, not cut, servings of this dish, being careful to keep the pine nuts on top.

Notes:
1. The gratin is a bit watery (I prefer to call it “juicy”). It’s just the nature of the zucchini. The liquid is actually infused with all the flavors of the gratin—thyme, onion, olives—and it wouldn’t be half bad (or bad at all) for dunking of bread. For cleaner serving, use a slotted spoon to avoid dinner plate puddles.
2. Inspired by and adapted from Deborah Madison’s The New Vegetarian Cooking for Everyone.