For the Cashew Cream
Rinse and drain the soaked cashew nuts. Add 2-3 tablespoons of water and blend the cashew nuts to a smooth paste. While blending, you may add 1 to 1½ tablespoons of arrowroot powder, to thicken the cream. To the smooth cashew cream, add salt to taste and crushed pepper.
For the Casserole
Steam the spinach, corn and button mushrooms (if using) with a bit of salt. Remove the kernels from the cob with fingers. Place the steamed spinach, corn and mushrooms in a casserole and add the cashew cream. Cook for a few minutes until the cream has thickened and coated the spinach-corn mixture. Add lemon juice just before serving.
You may add some herbs too.