Preheat the oven to 190 C
Make a deep cut in each pork fillet about three-quarters of the way through.
Crumble the Stilton and divide between each fillet, filling the cuts evenly. Slice the sage leaves and place these into the cuts as well. Season with salt and ground pepper.
Spread a piece of cling film on your work surface and lay out half the rashers (overlapping slightly) to match the length of your pork fillet. Lay the stuffed pork on the bacon and, using the cling film, roll the pork up in the bacon. Your pork roll should stay closed, but if not, tie with string in two places.
Heat the oil and butter in a frying pan and sear the pork roll for a couple of minutes until the bacon has coloured slightly. While this cooks repeat the previous step with the second fillet and seal this on the frying pan.
Cook in the oven for about 25 minutes and leave to stand for 10-15mins.