Summer Squash Gratin with Tomatoes, Parmesan and Fresh Thyme

Recipe by Tracy K
READY IN: 1hr 40mins




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