This takes time, a good ragu needs around 2 to 3 hours cooking, so don’t rush it. You can make a saving in time by getting the ragu going and then popping it in a low oven to simmer for a couple of hours just giving it the occasional stir, but don’t try and shorten the cooking time too much, it needs it to transform it into something truly special. If you can’t get the pork skin you can leave that out, but it will be richer and more unctuous if you can get some.