Tomato-Zucchini Slab Pie

Serves 6

This elegant tomato pie combines fresh tomatoes, zucchini and caramelized onions. An optional layer of provolone cheese hides under the tomatoes. To prevent the crust from getting soggy, the zucchini is cooked before being added to the pie.

Note: You can prepare the zucchini and caramelized onions the day before you plan on baking the pie. Store cooked zucchini and onions in the refrigerator overnight.


  • 2½ cups gluten-free flour (I used Bob's Red Mill Gluten-Free 1-to-1 Baking Flour)
  • 1 teaspoon salt
  • 1 cup (2 sticks) cold unsalted butter or shortening, cut into tablespoon-size pieces
  • 6 tablespoons ice water, plus additional as needed
  • 1 tablespoon olive oil, divided
  • 1 small zucchini, sliced into thin coins
  • 2 medium onions, sliced
  • ½ teaspoon salt
  • 8-10 slices (about 6 ounces) provolone cheese, optional
  • 3 large tomatoes, sliced
  • ¼ cup Parmesan cheese, optional
  • 6 leaves fresh basil, finely chopped


Prepare the crust: In the bowl of a food processor, combine flour, salt and butter. Pulse until mixture resembles a coarse meal and no large pieces of butter remain.

Turn the mixture into a large bowl. Stir in the water with a wooden spoon until a dough forms. You might need to squeeze the dough gently to get it to hold together. If it doesn’t, add water, one tablespoon at a time, until a dough forms.

Roll dough between two pieces of parchment paper into a 13- by 18-inch rectangle. Gently fold dough in half (it’s OK if it cracks) and transfer to a 15x10x1-inch jelly roll pan. Unfold dough, pressing it together wherever cracks appeared. Trim edges with a sharp knife. Crimp with a fork, if desired.

Cover pan with a piece of plastic wrap. Chill for 2 hours or overnight.

Prepare the filling: Heat half the oil in a large nonstick skillet over medium-high heat. Add zucchini in one layer and cook until golden brown. Turn zucchini over. Repeat until slices are lightly golden brown. Transfer zucchini slices to a plate. Wipe out pan and return to the burner.

Heat remaining oil over medium-low heat. Add onion slices and salt. Cook, stirring occasionally, until onions are soft and tender, about 30 minutes.

Make the pie: Preheat oven to 425° F. Adjust oven rack to middle position.

Remove plastic wrap from crust. Bake crust until lightly golden brown, about 15 minutes. Remove crust from oven and place on a wire rack. Keep the oven on.

Allow the crust to cool for a few minutes. Spread onions evenly over the bottom of the crust. Top with provolone slices, if using. Depending on the size of your slices, you might need to split a few in half so the crust is evenly covered.

Place the sliced tomatoes and cooked zucchini in one layer over the cheese. Sprinkle Parmesan over the tomato and zucchini slices, if using. Return pan to the oven and bake until cheese melts and tomatoes look soft, about 15 minutes.

Remove pan from the oven and place on a wire rack. Allow to cool for 15 minutes before slicing. Sprinkle chopped basil over the pie.

Nutrition Analysis: 550 cal, 34 g fat, 80 mg chol, 610 mg sodium, 57 g carbs, 2 g fiber, 5 g sugar, 5 g protein