1) Preheat oven to 190C/Gas 5.
2) Press the crust into the bottom and up the sides of a 20cm, removable-bottom tart tin. Set aside.
2) In a large bowl, combine spinach and stir-fried vegetables, and place on top of the uncooked crust. In another bowl combine the ricotta, Cheddar, milk, eggs, Dijon, oregano, salt and black pepper. Mix well. Spoon cheese mixture on top of vegetable mixture in prepared crust and top with Parmesan.
3) Bake for 20 minutes, until a knife inserted near the centre comes out clean and the crust is golden brown.