You can put the casserole together ahead of time and bake it just before serving. Start with it at room temperature, if possible, and bake it long enough to be sure it’s heated through. If it starts to get too brown on top, cover it with aluminum foil until it’s hot.
Instead of chickpeas, substitute any one of the following:
1 cup dry soy curls, rehydrated in hot vegetable broth and drained
2 cups baked tofu, cubed
1 1/2 cups tempeh bacon
1 1/2 cups sliced or diced seitan
Nutrition (per serving, no optional ingredients): 288 calories, 34 calories from fat, 4.2g total fat, 0mg cholesterol, 305mg sodium, 383.2mg potassium, 50g carbohydrates, 5.2g fiber, 4.3g sugar, 17.9g protein.