Preheat oven to 350 degrees F (175 degrees C). Grease a 9-inch pie plate.
In a medium bowl, mix together the margarine, flour, and salt until crumbly. Stir in the cold water until a dough forms.
Press the dough into the prepared pie plate.
In a large bowl, mix together the vegan sausage crumbles, tofu, nutritional yeast, onion powder, garlic powder, salt and pepper. Sprinkle the cornstarch over the mixture and stir to combine.
Spread mixture into the prepared crust.
Bake in preheated oven for 30 minutes or until golden brown.