Preheat the oven to 350 degrees F. Generously coat a 9-inch round springform pan with vegan margarine.
Put the regular tofu, silken tofu, nondairy milk, salt, turmeric, garlic powder and pepper into a blender or food processor and process until smooth.
Fold in the vegan cheddar cheese, Italian seasoning and onion, using a rubber spatula. Transfer the tofu mixture to the prepared pan and smooth the top with the back of a rubber spatula. Arrange the 14 asparagus spears to resemble the spokes of a wheel, with the asparagus tips forming the center of the “wheel.”
Top the quiche with several grinds of black pepper. Bake for 45 to 55 minutes, or until the center of the tart is quite firm to the touch. Put the pan on a wire rack and let cool 5 minutes.
Gently run a table knife around the perimeter of the tart to loosen it from the sides of the pan. Let cool for 5 to 7 minutes, then carefully remove the outer ring of the springform pan.
Let the tart cool for 30 minutes more before serving (see note). Alternately, cover the tart and refrigerate for 4 to 6 hours, or until well chilled, and serve cold.