Total Time
2hrs 10mins
Prep 1 hr
Cook 1 hr 10 mins

While this recipe calls for summer vegetables, my brother and SIL prepared it for Christmas dinner 2009 and I loved it. Good as a vegetarian main dish or a side. It's not quite the same as other vegetable gratins already on RecipeZaar. Personally, I would make this with less olive oil, the amount of which I specified in the ingredients, but you can use the original amount if you prefer (just convert teaspoons to tablespoons). This can also be made ahead after assembly and before baking. Just pre-heat the oven. Try to buy the zucchini and squash of roughly the same diameter. I might serve this with bread to soak up the juices. To make this vegan, omit the parmesan cheese. They found this recipe on America's TV test kitchen.

Ingredients Nutrition


  1. Adjust oven rack to upper-middle position and heat oven to 400 degree. Brush 13- by 9-inch baking dish with 1 teaspoon oil; set aside.
  2. Toss zucchini and squash slices with 1 teaspon salt in large bowl; transfer to colander set over bowl. Let stand until zuccchini and squash release at least 3 tablespoons of liquid, about 45 minutes. Arrange slices on triple layer paper towels; cover with another triple layer paper towels and firmly press each slice to remove as much liquid as possible.
  3. Meanwhile, place tomato slices in single layer on double layer paper towels and sprinkle evenly with 1/2 teaspoon salt; let stand 30 minutes. Place second doube layer paper towels on top of tomatoes and press firmly to dry.
  4. Meanwhile, heat 1 teaspoon oil in 12-inch non-stick skillet over medium heat until shimmering. Add onions, remaining 1/2 teaspoon salt, and 1/4 teaspoon pepper; cook, stirring occasionally, until onions are softened and dark golden brown, 20 to 25 minutes. Set aside.
  5. Combine garlic, 2 teaspoons oil, remaining 1/2 teaspoon pepper and thyme in small bowl. In large bowl, toss zucchini and squash in half of oil mixture, then arrange in greased baking dish. Arrange caramelized onions in even layer over squash. Slightly overlap tomato slices in single layer on top of onions, Spoon remaining garlic-oil mixture evenly over tomatoes. Bake until vegetables are tender and tomatoes are starting to brown on edges, 40-45 minutes.
  6. Meanwhile, process bread in food processor or belender until finely ground (about 10 seconds). You should have about 1 cup crumbs. Combine bread crumbs, remaining teaspoon oil, parmesan and shallots in medium bowl. Remove baking dish from oven and increase heat to 450 degrees. Sprinkle bread crumb mixture evenly on top of tomatoes. Bake until bubbling and cheese is lightly browned, 5-10 minutes. Sprinkle with basil and let sit at room temperature 10 minutes before serving.
Most Helpful

5 5

Hubby put both thumbs up for this one! Definitely a five star! Delicious and love the colors in this. I used the smallest amount of oil I could. Thanks for posting Kumquat! Made for Photo Swap 8. Did make this ahead to fit our schedule, think you should add that category.

5 5

This recipe was awesome. I made it for a dinner party and everyone enjoyed it - even those who are not crazy about squash (like me). I agree that the original amount of olive oil would have been too much. I didn't have fresh thyme, so I used a Rosemary herb seasoning mix from Pampered Chef and it was delicious. I also used plum tomatoes. It does take a lot of preparation, but it is worth it. I will definitely make this again.

5 5

I saw this in Cook's Illustrated and really wanted to make it. Other than using about 1/2 roll of paper towels, I loved this! Great flavor, wonderful color. The fresh taste of the vegetables really comes shining through.

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