Heat your oven to 220C°/Fan 200°C/Gas 7. Pat the pork tenderloin dry with kitchen paper. Place in a large roasting tin and rub all over with 1 tbsp oil and a pinch of salt and pepper. Slice the cherry tomatoes in half and scatter around the pork. Slide into the oven and cook for 15 mins till the pork is cooked through. Set aside on a warm board or plate, loosely covered with foil, to rest while you finish the rest of the dish.
While the pork and tomatoes roast, peel the onion and finely chop. Peel and crush or finely chop the garlic clove. Pick the thyme leaves. Strip the kale from the tough stalks. Discard the stalks and finely shred the leaves.
Pour 1 tbsp oil into a large pan and bring to a medium heat. Slide in the onion, garlic and thyme, and add a little salt and pepper. Fry for 2-3 mins, stirring occasionally, till slightly softened.
While the onions fry, pour 800ml boiling water into a pan and bring to a simmer. Crumble in the stock cube and stir well to dissolve.
When the onion is soft, turn the heat under the pan up a little and tip in the rice. Stir well, coating the rice in the hot oil, for 1-2 mins, till the rice starts to make a slight popping sound. Pour in 1 ladleful of hot stock and stir till all of the stock has been absorbed by the rice.
Repeat the stock ladling and stirring process till only 1 ladleful of liquid remains and the rice is swollen and nearly cooked – about 20 mins. At this point, stir in the shredded kale and the remaining stock and stir for a further 2 mins, till the leaves have wilted.
Squeeze in the juice from half the lemon. Grate in most of the parmesan. Have a taste of the risotto and sprinkle in a little more salt or pepper if you think it’s needed.
Spoon the risotto onto warm plates. Thinly slice the pork and serve on top of the kale risotto with the roast cherry tomatoes and spoon over some of the juices from the roasting dish. Finish with a few gratings of remaining parmesan and serve.