Vegan Provençal Quiche with Heirloom Tomatoes, Olives, and Fresh Basil

This vegan quiche is gorgeous and full of summery tomato-basil-olive flavor. Although it takes about four hours to prepare from start to finish (including chilling time), the dish is well worth it for a festive brunch or summer lunch.

• 1 1/2 cups plus 3 tablespoons white whole wheat flour, divided

• Scant teaspoon coarse kosher salt, divided

• 1 stick (8 tablespoons) plus 3 tablespoons vegan butter, chilled and cubed

• 1 tablespoon flaxseeds, finely ground

• 6 tablespoons ice-cold water

• Cooking spray

• 1 tablespoon olive oil

• 2 cups very thin slices red onion (about 2 small)

• 7 very thin slices heirloom, beefsteak, or hothouse tomato, ideally in 2 to 3 colors

• 1 12-ounce package plain extra-firm tofu, drained

• 1/4 cup chopped fresh chives

• 3 tablespoons plain unsweetened cashew milk

• 2 tablespoons plus 1 teaspoon green olive tapenade or spread (without anchovies), divided

• 2 teaspoons fresh, strained lemon juice

• 2 teaspoons cider vinegar

• 1 1/2 teaspoons agave nectar

• 1 teaspoon Dijon mustard

• 4 grinds black pepper

• About 8 fresh basil leaves

In a medium bowl, whisk together 1 1/2 cups plus 1 tablespoon of the flour and 3/4 teaspoon of the salt until thoroughly mixed. Add the butter, and crumble together until the mixture forms coarse meal. In a small bowl, whisk together the flaxseeds with the ice-cold water. Add to the flour, and massage the dough until it forms a ball. Wrap in plastic, and flatten into a 1-inch-thick disk. Chill for at least 30 minutes in the fridge.

Spray the inside of a 9 or 9 1/2-inch fluted tart pan with a removable bottom with cooking spray. Sprinkle the remaining 2 tablespoons of flour onto a large, clean, cold surface. On this surface, roll the dough into a circle roughly 12 inches in diameter. After each roll, rotate the dough a quarter turn. Transfer the dough circle to the tart pan. Press it into the bottom and sides, rolling the rolling pin over the surface to remove any excess dough (which you can use for patching holes). Cover with plastic wrap and chill for at least 30 minutes. Meanwhile, preheat the oven to 400 degrees F.

Place the tart shell on a baking sheet. Spray a large piece of aluminum foil with cooking spray and place the foil, spray side down, onto the dough in the tart pan. Top with dried beans or pie weights. Bake for 20 minutes. Remove from the oven and take off the foil and weights (discard the foil). Use a fork to poke about 15 holes in the bottom of the shell. Return to the oven, and bake until very lightly golden, about another 10 minutes (the crust may shrink a bit).

Meanwhile, brush the inside of a 10-inch nonstick skillet with oil, and heat over medium. When the oil is warm, add the onions, and saute for 10 minutes, stirring occasionally. Reduce the heat to low, and continue cooking until the onions are very limp, about another 10 minutes (watch carefully—you don’t want the onions to turn dark brown or black). Place the tomato slices on a large, clean kitchen towel and sprinkle evenly with the remaining salt (a scant 1/8 teaspoon). Cover with another clean kitchen towel and let sit to drain for at least 20 minutes. In a mini food processor, puree the tofu, chives, cashew milk, tapenade, lemon juice, vinegar, agave nectar, mustard, and pepper until smooth, about 1 minute.

Reduce the oven temperature to 350 degrees F. Pour the custard into the shell, and spread evenly. Sprinkle evenly with the caramelized onions. Overlap the tomato slices around the perimeter of the tart and place one slice in the center.

Bake until the inside is set (doesn’t jiggle), about 45 minutes. Let cool for about 10 minutes, and carefully remove the ring from the tart pan. To do this, lift the tart from the bottom, allowing the ring to fall off. Ideally, chill for at least an hour to allow the filling to further set. Top with the basil.