Preheat your oven to 160C / 140C fan / gas mark 3 / 325F.
Drizzle 2 tablespoons of olive oil into a large ovenproof saucepan or cast iron casserole dish. Add the onions and cook on a gentle heat, with the lid on, for about 3 minutes, until the onions are softened but not brown.
If you don’t own an ovenproof saucepan or cast iron casserole dish, simply cook the stew in a regular saucepan up until it has to go in the oven and then transfer the stew into a regular lidded casserole dish before placing in the oven. Add on an extra 5 minutes cooking time to allow for the fact that the casserole dish will need extra time to heat up.
If you can't get hold of suet, use the same quantity of butter instead.
Suitable for freezing. (Freeze dumplings and stew separately)
Nutrition information is approximate and meant as a guideline only.