Preheat oven to 400F. Oil a 2-quart casserole dish. Cut the potatoes into quarters (1/2-inch cubes if they’re large). Place them on a baking sheet lined with a silicone mat or parchment paper. Roast for 15-20 minutes, stirring once, until they are slightly tender and beginning to brown. Remove from oven and transfer to the casserole dish. Season lightly with salt and pepper. Sprinkle with the roasted red pepper.
While the potatoes are baking, prepare the broccoli rabe. Bring a large pot of water to a boil and have ready a large bowl of water and ice. Cut off and discard the broccoli rabe’s thick stems. Chop the leaves and smaller stems into 2-inch pieces. Add about a tablespoon of salt to the boiling water and add the broccoli rabe. Return to a boil and cook until the rabe is tender, about 5 minutes. Drain well and plunge into the prepared ice water. Keep it in the ice water until the potatoes are in the casserole dish. Then, drain the water and dry the greens as best you can (spinning them in a salad spinner helps). Put them on top of the potatoes and sprinkle with salt and pepper if desired.
Place tofu and remaining ingredients in a blender, and puree until very smooth. Pour over the broccoli rabe. Use a spoon to gently open holes through the greens so that the tofu mixture penetrates it. Smooth the top so that tofu layer is even and covers all the rabe.
Bake for 40-50 minutes, or until liquid has thickened. (Shallow baking dishes will take less time than deep ones.) Remove from oven and allow to rest for 10 minutes before slicing and serving.
Without the optional cashews, one serving is 3 points on Weight Watchers Freestyle program.