Ultra-quick gravy for special occasions, that meat-eaters won't even realise is veggie. Good in and on pies, mixed veggies, pasta and more.
Tahini can be expensive, so for larger quantities use cornflour to thicken the gravy. You can use Vecon® instead of Marmite®, or cow's milk to replace some, or all of the water. Depends what you're serving it with.