Skink is what they call beef shin here. It´s the cheapest cut at my local butcher´s, and a very good one, too, beefy and strong and just the thing for a stew with a lot of sauce. Even better, you get to scoop out the marrow from the bones, and better still, I brook no argument; in this house, the marrow is for me, la mamma.
Most recipes will tell you to brown then braise for a long time, and of course you should do that in the best of all possible worlds. But life is too short to brown beef, and a pressure cooker will ensure you can have the meat on the table in not very long. Leave the other stuff to the overachievers and the proffesionals.
I suggest you follow the method for your favourite beef stew, or this recipe, only do it in the pressure cooker and give it 35 minutes under pressure, then let it come down naturally before you unlock the lid.
Two pieces of about half a kilo each should serve four, provided you serve this on top of some starchy stuff that mops up the wonderful sauce. Just remember to cut the sides so the meat doesn´t curl up.
If you have any left over, here are some ideas.