This is from another user on minimins.
Syn Free on all plans (Red, Green or Extra Easy
1 large red onion, finely chopped
2 cloves of garlic, crushed
few sprigs of fresh thyme (or other herbs of your choice)
500ml of beef stock (I just use a couple of oxo cubes)
splash of balsamic vinegar
Frylight or Pam spray
Spray a large saucepan with some Frylight or Pam Spray.
Add the onion and garlic and cook until golden. You may need to add a little of the stock if it starts to stick.
Add the fresh herbs, stock, and a splash of balsamic vinegar, bring to the boil and reduce heat. Allow to simmer covered for approx 1.5 hours (this really brings out all the flavours, but you can cook it for a shorter time period if you need to.)
When it has cooked for required time, blitz with a hand blender and your gravy is ready to serve. It is great with any meat or sausages or can even be used for the sauce for a shepherds pie or similar.