Summer Squash Gratin with Tomatoes, Parmesan and Fresh Thyme

READY IN: 1hr 40mins
Recipe by Tracy K

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

Top Review by sugarpea

Other than zucchini cake slathered with hard sauce, I think this is the best summer squash dish I've ever had. You just ahve to be patient, as Tracy advises, and cook until the juices have reduced and the veggies have carmelized a bit. 27*, Tracy.

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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