Preheat the oven to 200°C. Place the ribeye in a roasting pan and add 4 chopped cloves garlic, 1/2 teaspoon fennel seeds, 2 sprigs rosemary, 1 chopped onion, 1 x 400g can crushed tomatoes, 4 tablespoons maple syrup and 200mls chicken stock. Drizzle the top with a little olive oil. Season and place in the oven for 1 1/2 -2 hours or until the juices run clear when a small knife is inserted into the middle of the pork. (If it looks like it will burn before it is cooked, cover loosely with foil.)
Remove from the oven and remove the pork from the pan to a plate. Cover loosely with foil and rest 10-15 minutes. Mix the sauce in the pan, taste, and season if necessary.
Slice the pork and serve with the tomato sauce from the pan.