I have a large back of powdered stuff used in restaurants and it's slightly quicker to do, so I use that, but before I got access to the powder, I used the following recipe. It is from my home economics book, which it is for one portion only. The main advantage is that it won't have any nasty E numbers.
0.5 tbsp plain flour
2 tbsp cold milk or single cream
1 dl meat stock (= the fat from whatever meat was fried + water)
salt, black pepper, soy sauce
- Blend all ingredients and bring to the boil.
- Simmer for 5 minutes, until it thickens.