While the biscuits are baking, cook the vegan sausage in a skillet over medium heat, using a spatula to break it into pieces.
Add vegan butter to the skillet. Use a spatula to break it up into smaller pieces and cook until melted.
Sprinkle the flour over the melted butter and sausage while continually stirring. Cook for a few minutes until flour has completely absorbed the butter.
Turn heat down to medium-low and slowly add the vegetable broth, one cup at a time, stirring continuously. Sprinkle with nutritional yeast flakes, pepper, and salt. Stir to combine. Cook for approximately 5 minutes until the gravy has thickened.
Keep over low heat until ready to serve. Transfer gravy to a serving dish to serve immediately. Alternatively, place in a sealed container and refrigerate for up to 4 days. It can be frozen for up to 2 months. When reheating gravy, add water or broth if it gets too thick while reheating.
If you make the gravy ahead and reheat it, you may need to add additional vegetable broth to thin it out because it may thicken as it cools.