- Crust:
- 1 3/4 cups crushed chicken-flavored crackers (such as Nabisco® Chicken in a Biscuit)
- 6 tablespoons melted butter
- 1 egg white, beaten
- Filling:
- 3/4 pound boneless chicken breast, cut into small pieces
- salt and ground black pepper to taste
- 1 tablespoon olive oil
- 2 tablespoons butter
- 1/2 cup chopped shallot
- 6 ounces cremini mushrooms, thinly sliced
- 1 tablespoon minced garlic
- 2 teaspoons finely chopped fresh rosemary
- 1 cup heavy whipping cream
- 2 eggs
- 6 tablespoons grated Parmesan cheese, divided
- 1/4 cup finely chopped Italian parsley, divided
- 1/2 teaspoon salt
- 1/2 teaspoon ground black pepper
- Preheat oven to 350 degrees F (175 degrees C).
- Mix crushed crackers and melted butter together in a bowl; press into the bottom and up the sides of a 9-inch springform pan.
- Bake in the preheated oven for 10 minutes. Remove crust from oven and brush egg white onto the crust, to seal. Bake 4 minutes more. Remove from oven and cool to room temperature.
- Season chicken with salt and pepper.
- Heat olive oil in a heavy large skillet over medium heat; cook and stir chicken just until brown, about 2 minutes per side. Transfer chicken to a plate.
- Reduce heat under skillet to medium-low; add 2 tablespoons butter. Cook and stir shallot in the hot butter until beginning to soften, about 2 minutes. Add mushrooms, garlic, rosemary, and 1 pinch salt; cook and stir until mushrooms are tender and juices evaporate, about 8 minutes.
- Whisk cream, eggs, 1/4 cup grated Parmesan cheese, 2 tablespoons parsley, 1/2 teaspoon salt, and 1/2 teaspoon pepper together in a bowl.
- Place baked crust on a baking sheet; top with chicken and mushrooms. Pour egg mixture over top. Sprinkle remaining 2 tablespoons Parmesan cheese over the top.
- Bake in the preheated oven until top is lightly golden and middle is set, 30 to 35 minutes. Let tart rest for 10 minutes. Remove outer ring. Top tart with 2 tablespoons remaining parsley.