It's really involved LOL normally takes me a day to cook... (but that's including fresh pasta) but here ya go

1.5 kgs of oxtail or shin cut into 10 pieces (get your butcher to do this).
As much beef stock that will fill the SC
Zest of 2 oranges
Juice of 3
1 onion
about 12 garlic cloves
an egg
thyme
olice oil

Season then brown your pieces of meat. Then add to the slow cooker, Cook onion & about 8 garlic cloves (whole this is just for flavour) for a couple of minutes till translucent then add the whole lot to the slow cooker. Add Juice of 2 oranges (3rd one is for making ravioli mix) and stock and some twigs of thyme. Cook on low for about 8 hours or so. Then I remove the meat and let it rest till I can take it off the bone. Then I strain the liquid and put in a large pot and simmer till it's reduce by about 3/4 (this is the sauce for the ravioli). Then I get the meat add it to the food processor along with some cooked baby spinach (with garlic) some fresh parmesan (about a cup grated) the juice of the other orange an egg and a couple of tablespoons of olive oil. Blitz until combined. This is your filling for ravioli. Then make your ravioli, Saute some more baby spinach with garlic, boil your ravioli serve the ravioli on top of the spinach and then pour some of the reduced broth over the top and top with some more parmesan. This was a recipe I got from Martha Stewart... and I have also made it with egg wonton wrappers as pasta sheets and it's divine