I crave thick sauces

Three weeks in, and the only thing I am really missing is my thick sauces. Me menu planner says I can have 1 tablespoon of “sauce, gravy or brown, instant prepared” whatever that means??? Does it mean 1 tablespoon of gravy granules to which I can add water? When I make gravy I use Bisto gravy granules, I have quarter of a pint, and I use double the amount of granules so it goes nice and thick. Sauces made with double cream are also yummy… What am I allowed to do? I know Quark works quite well to make a creamy sauce and does not need sweetening like Greek yogurt, but am I allowed to use a knorr stock cube and thicken it with cornflour to make a gravy? Up to now I have been using water and the free flavours (like soy sauce, lemon juice, yeast extract, garlic, ginger, herbs and spaces, etc.) but I like my sauce to stick to my food rather than leave a pool of water on the plate.