Vegan Quiche

Preheat oven to 425°F. Fit pie crust into a 9-inch pie pan; fold edges under and crimp. Prick the bottom and sides of the crust with a fork; bake until lightly browned and set, 8 to 10 minutes. Transfer to a wire rack to cool completely, about 30 minutes. Reduce oven temperature to 350°F.

Meanwhile, heat oil in a large nonstick skillet over medium heat. Add leek; cook, stirring occasionally, until softened, 4 to 5 minutes. Add mushrooms, garlic and 1/4 teaspoon salt; cook, stirring often, until the mushrooms are tender, 5 to 7 minutes. Add spinach; cook, stirring constantly, until wilted, about 1 minute. Transfer the mixture to a large bowl to cool slightly, about 15 minutes.

Combine tofu, nutritional yeast, oat milk, turmeric, pepper, cayenne and the remaining 3/4 teaspoon salt in a food processor. Process until smooth, stopping to scrape down sides as needed, 30 seconds to 1 minute. Transfer the mixture to the bowl with the vegetables. Add cheese and stir to combine.

Spoon the mixture into the cooled pie crust and smooth the top. Bake until the filling is set, 35 to 40 minutes. Let cool on a wire rack for 15 minutes. Serve warm.