Summer Vegetable Gratin

This colorful dish used my entire CSA box in one meal! My husband accepted it as a vegetarian main because of the flavorful baguette-cheese topping (yay!), but it would also work well as a hearty side dish. We even had a green salad on the side. 🙂

This recipe was adapted from The New York Times, contributed by Julia Moskin. Moskin recommended using a fresh baguette in the topping for the best crust. Great!

Yield: Serves 6 to 8 as a main dish or up to 12 as a side dish

Time: 1 1/2 hours

For the Base Layer:

• 2 medium onions, thinly sliced
• ¼ cup olive oil
• 2 red bell peppers, thinly sliced, or 2 additional onions
• ½ teaspoon red pepper flakes
• 8 cloves garlic, smashed

For the Tomato-Bread Crumb Topping:

• 1 ½ pounds plum or other ripe tomatoes
• ¼ cup olive oil
• 1 baguette
• 1 cup shredded Parmesan or Gruyère cheese

For the Gratin:

• ¼ cup olive oil, more for baking
• 1 ½ pounds zucchini, sliced 1/4-inch thick (I used 2 pieces)
• 1 ½ pounds yellow squash, sliced 1/4-inch thick (I used 2 pieces)
• ¼ cup freshly chopped basil or parsley, more for garnish
• coarse salt and freshly ground black pepper

1. Make the base layer: In a large, heavy ovenproof skillet or enameled cast-iron pan (10 to 12 inches across), combine onions and olive oil and heat to a sizzle, stirring to separate.
2. Add bell peppers, red pepper flakes and garlic. Cook, stirring, over low heat until peppers are very soft and onions are browned, about 20 minutes. Season with salt and pepper. Remove from heat and leave mixture in the pan. (The garlic can be removed at this time, if desired.)
3. Meanwhile, make the topping: Core tomatoes and slice them 1/4 inch thick. Lay on paper towels to drain for 10+ minutes.
4. Heat 2 tablespoons oil in a large skillet over low heat. Add tomatoes and cook very slowly, turning once or twice, until liquid has bubbled away and flesh is cooked through, about 8 minutes. (Do not overcook, or tomatoes will fall apart.) Turn off heat and let slices cool in skillet; they will continue to dry out.
5. Tear baguette into pieces and pulse in a food processor to make coarse, fluffy, pea-size crumbs. Add remaining 2 tablespoons oil and the cheese and pulse to combine.
6. Assemble the gratin: Heat oven to 425 degrees. (If your oven has a convection feature, use it, reducing baking temperature to 400 degrees.)
7. In a large bowl, combine oil, zucchini and squash, and toss well until lightly and evenly coated. Add basil, sprinkle generously with salt and pepper, and toss again.
8. On top of the base layer in pan, arrange squash and zucchini slices around the inner rim of the pan, standing on their edges in roughly alternating colors. Pat down into the pan so slices overlap and lie down, like shingles or fallen dominoes. Repeat to make another circle inside the first, and again if necessary, until pan is filled. Sprinkle with salt and pepper. 
9. Brush oil over the top of the gratin and transfer to oven. Bake 30 minutes. Raise oven temperature to 450 degrees (425 degrees for convection), or heat the broiler.
10. Add the topping: Arrange tomato slices in one layer on top of the par-baked gratin. Spread bread-cheese mixture over tomatoes and press down gently.
11. Bake or broil until vegetables are browned around the edges or crust is crisp and golden. 
12. Let cool slightly and serve hot or at warm room temperature. Garnish each serving with herbs, if desired.

One Year Ago:

• Falafel-Spiced Heirloom Tomatoes & Chickpeas on Flatbread
• Ritzy Summer-Squash Casserole

Two Years Ago:

• Ina Garten’s Provencal Tomatoes

Three Years Ago:

• Escalivada or Grilled Vegetable Salad with Parsley Vinaigrette
• Panzanella with Ricotta

About Josette@thebrookcook

I live in Stony Brook, New York on Long Island. I love garlic and baking. My hobby (and love) is to try new recipes. My favorite recipe resources include The New York Times, Food and Wine, Bon Appetit, and Martha Stewart Living. Enjoy!

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