Soak cashew nuts for at least 1 hour. Overnight is best. The longer they soak, the creamier the ricotta will be. Drain soaked cashews and combine with other cashew ricotta ingredients in a small blender and process until smooth, creamy texture. Add more water if needed. Set aside.
Heat cooking oil in a pan/skillet over medium-low heat. Stir in bell pepper and cook for 2 minutes.
Then add Chinese and red cabbage and mix well. Cook for 2-3 minutes or until cabbage starts to release its water. (Make sure that cabbage is not overcooked and maintains its crunchy texture).
Add cashew ricotta cheese to the cabbage mix and stir well to combine. Add oregano, salt, and pepper to taste, mix well and cook for another 2 minutes.
Spoon the mixture on a slice of bread. Cover it with another slice of bread.
Optional: grill using a sandwich/panini maker or under the oven grill. Or you can also toast the bread first and stuff with the filling since the filling is already cooked.