Heat the oil over a medium heat, then add the onion and garlic, stirring for a couple of minutes to soften.
Put in the ribs, turn up the heat and move around with a wooden spoon to brown all over.
Add the carrots, swede and mushrooms. Put in the herbs and season to taste.
Pour in the wine and bring to the boil, stirring well. Put on the lid and cook under high pressure for 40 minutes.
Quickly cool the sides of the cooker under running water before removing the lid and adding the potatoes.
Check the seasoning then return to high pressure for another 10 minutes. Serve with green vegetables of your choice.