Peel and chop the onion and garlic.
Peel the potatoes, then cut into small cubes.
Heat 2 Tbsp of oil in a saucepan, then at low heat gently fry the onion and garlic until softened. Add the potatoes, stir for 3 minutes, then pouring the stock. Bring to the boil and cook for 10-15 minutes until the potatoes are tender.
Meanwhile, slice the cabbage into thin strips.
Take the soup off the cooker and slightly crush the potatoes with a masher. Put it back on the heat and add the cabbage strips. Bring to the boil and simmer under cover for 5 minutes.
Meanwhile, slice the sausages and fry them in the remaining oil on both side until golden.
Mash through the soup again - but don't overdo it, it should not be smooth!
Serve with the fried sausage slices and drizzle with its released fat.