Pre heat oven to 190C/475F
If making the quiche crust, mix together the flour, the add water and oil and mix well. Knead until smooth then cover and let rest while you prepare the filling.
To make the tofu sauce: blend tofu, milk, walnuts, nutritional yeast. Blend until smooth (add some water/milk if not) then season with salt and pepper.
In a pan saute a small red onion in a little olive oil then add finely chopped radicchio, sprinkle with some salt and let wilt. When it’s soft, turn off the heat and remove any excess water. Add the tofu sauce to the pan and mix to combine.
Prepare the crust into a pie oven safe, makes some holes with a fork and pour the mixture in it. Spread evenly and top with some more crumbled walnuts, and season with salt and pepper.
Bake for 30 minutes or until golden.