Sausage and Onion Casserole for the Slow Cooker

Sausage and onion casserole made in a slow cooker.
A comforting family casserole made from scratch. With sausages slow cooked in a rich onion and tomato gravy. Serve with mash and veg.

See my recipe note for a shortcut using ready-made seasonings.

For more slow cooker UK recipes using sausages, see my posts included below.

Sausage and Onion Casserole – UK Slow Cooker Recipe

Ingredients (Serves 4)

450 g good quality pork sausages.
1 tbsp vegetable oil.
2 red onions, cut into medium thickness half-moon slices.
1 tbsp balsamic vinegar.
1 tbsp flour.
500 ml hot beef stock.
4 tbsp ketchup, spicy or regular.
Salt and pepper.
Pinch of sugar, optional.

I made this slow cooker sausage and onion casserole recipe in a Morphy Richards Accents Sear and Stew 3.5 L Slow Cooker (See my review).

Method (Total Cooking Time: 3 to 5 hours on High or 6 to 8 hours on Low)

Brown the sausages on all sides, in the oil, on medium high heat. For about 5 minutes, without cooking through. Place in the slow cooker pot.
In the same frying pan, on medium heat add the onions. Fry until slightly golden and soft, about 5 mins. Add the vinegar, (carefully as this will spit a bit). Then add the flour, stir until it has been absorbed. Allow it to cook out for 2 minutes.
Add the stock, stir and bring to the boil. Add the ketchup, salt, pepper and sugar, if needed. Check and adjust the seasoning.
Pour this onion gravy over the sausages in the slow cooker. Cover with lid. Cook High for 3 to 5 hours. Or on Low for 6 to 8 hours.
Serve with mashed potatoes. And seasonal vegetables.

Recipe Notes

If you are short of time or space, you could also use this shortcut: Colman’s Sausage Casserole Recipe Mix*. Which includes all of the flavourings for this sausage casserole, in a handy sachet. And is made specifically for the slow cooker.