Summer Squash Gratin with Tomatoes, Parmesan and Fresh Thyme

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“Delicious veggie dish with intense flavor. Suitable as a main course for a light meal, or a fantastic summer side dish. A shallow oval gratin dish will give you the best results, but a shallow casserole dish will work as well, just be certain to cook it until the veggies have shrunken and the juices have reduced. Source: Fine Cooking”
1hr 40mins

Ingredients Nutrition


  1. Preheat oven to 375.
  2. To cook the onions-- In a medium skillet, heat the olive oil over medium heat.
  3. Add the onions and sauté, stirring frequently, until limp and golden brown, about 2 min.
  4. Reduce the heat to medium-low if they're browning too quickly.
  5. Add the garlic and sauté until soft and fragrant, 1 to 2 min.
  6. Spread the onions and garlic evenly in the bottom of an oiled 2-qt. shallow gratin dish (preferably oval).
  7. Let cool.
  8. To assemble the gratin: Put the tomato slices on a shallow plate to drain for a few minutes and then discard the collected juices.
  9. In a medium bowl, toss the zucchini and squash slices with 1-1/2 Tbs. of the olive oil, 2 Tbs.of the thyme, and 1/2 tsp.of the salt.
  10. Reserve half of the cheese for the top of the gratin.
  11. Sprinkle 1 Tbs.of the thyme over the onions in the gratin.
  12. Starting at one end of the baking dish, lay a row of slightly overlapping tomato slices across the width of the dish and sprinkle with a little of the cheese.
  13. Next, lay a row of zucchini, overlapping the tomatoes by two-thirds, and sprinkle with cheese.
  14. Repeat with a row of squash, and then repeat rows, sprinkling each with cheese, until the gratin is full.
  15. Season lightly with pepper and the remaining 1/2 tsp.salt.
  16. Drizzle the remaining 1-1/2 Tbs.olive oil over all.
  17. Combine the reserved cheese with the remaining 1 Tbs. thyme and sprinkle this over the whole gratin.
  18. Cook until well-browned all over and the juices have bubbled for a while and reduced considerably, 65 to 70 min.
  19. Let cool for at least 15 min.before serving.
  20. NOTE: You can use any combination of summer squash for this dish.

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