Sauté the onions in the butter and olive oil until soft and caramelised.
Add the flour to form a roux and stir until cooked out, then gradually stir in 1 pint of stock - you can use vegetable, beef, pork or chicken.
Add a splash of Port, Cider or Cider Vinegar and simmer until thickened.
https://www.donaldrussell.com/rich-onion-gravy.html29242Rich Onion Gravyhttps://www.donaldrussell.com/media/catalog/product/g/r/gravy_4.jpg00GBPInStock/Guides/Accompaniments/Other sauces/Guides/Recipes/Christmas recipes & guides289610<p>Our delicious, rich gravy</p> <p>The ultimate accompaniment for so many beef dishes is a rich onion gravy. Tangy flavours combine in a rich onion gravy recipe that is a pleasure to eat.</p>GBP00https://www.donaldrussell.com/media/catalog/product/g/r/gravy_5.jpgRD1072recipe-£0.00 per kgNoCondiments & SaucesBeef, Chicken, Other Poultry