In a small pot on medium heat: add the olive oil, flour, porcini mushroom powder, garlic and onion powder. Stir well to combine, and cook for a couple of minutes.
Slowly incorporate the vegetable stock, stirring vigorously to remove any clumps. Bring the mixture to a soft boil until the gravy thickens.
Stir in the tamari. Remove from the heat and allow to cool down for 5 minutes before serving.
