Heat the oil in a large frying pan over medium heat. Sweat the onions with the salt for 6-7 minutes or until softened. Add the cannellini beans, pour in the wine and cook over a medium-high heat for 4-5 minutes until the liquid has reduced by half, then season. Cook the tortellini according to the instructions on the pack and drain, reserving a large ladleful of the pasta cooking water. Add the pasta and cheese the to pan with the onions and toss gently before adding the rocket. Give it all another stir and add the reserved pasta water a little at a time to loosen the sauce, if it needs it. Divide the pasta between 4 bowls and finish with a little more cheese. *You can also make this recipe with Rana Chicken & Pancetta Tortelloni.