For the filling:
3 tablespoons medium extra-virgin olive oil, divided
2 medium onions, chopped
4 medium zucchini, cut in 1/2-inch half-moons
2 tablespoons sorghum flour or other whole grain flour
1/4 teaspoon ground nutmeg
Fine sea or Himalayan salt to taste
Freshly ground pepper to taste
3/4 cup hot unsweetened nondairy milk (see Note)

For the topping:
1/2 cup chopped walnuts
1/4 cup sorghum flour or other whole grain flour
2 tablespoons large-flaked nutritional yeast
Fine sea or Himalayan salt to taste
Freshly ground pepper to taste
2 tablespoons medium extra-virgin olive oil

Preheat the oven to 400 degrees F. Have a 9-inch deep dish pie dish ready.

To make the filling, heat 2 tablespoons olive oil in a large skillet over medium heat. Add the onions, cooking until softened and translucent, about 8 minutes. Add the zucchini and cook until softened, about 8 more minutes. Add the remaining oil, mixing well. Stir in the flour, nutmeg, and a few dashes of salt and grinds of pepper. Mix to coat. Slowly pour in the hot nondairy milk while stirring. Let cook until thickened, about 5 minutes. Scrape the mixture into the prepared dish.

To make the topping, put the walnuts, flour, nutritional yeast, and a few dashes of salt and grinds of pepper in a food processor. Process until mixed and the walnuts are coarsely ground. Add the oil. Process for about 30 seconds until the mixture can stick together when squeezed in fingers. Evenly sprinkle the mixture over the zucchini.

Bake for about 16 to 18 minutes, until bubbly and the topping has browned. Let cool at least 20 minutes before serving, though it will thicken more as it stands. Serve warm or at room temperature.

Note: The best option for nondairy milk in this recipe is coconut milk beverage (in the carton), as it is fattier and richer, has produces a creamier (but neutral tasting) result.