To make the pesto; drop the Broccolini® into a saucepan of boiling salted water. Cook 2 minutes or until bright green. Drain. Refresh in cold water. Pat dry with a paper towel then roughly chop. Place the Broccolini® into a food processor with basil, chilli and garlic. Pulse until finely chopped. Add cashew nuts, pulse until well combined. Combine the olive oil and grapeseed oil in a jug. With the processor running, add the oil in a slow and steady stream until all the oil has been incorporated. Transfer pesto to a bowl. Stir in pecorino. Season.
Heat the oil in a saucepan over medium heat. Add the onion and garlic and cook 2 minutes until the onion is soft. Add the fresh and canned tomatoes, season well. Cook, for 20 minutes or until tomatoes soften.
Cook the pasta in a large saucepan of boiling salted water for half the time recommended on the packet, the pasta needs to be firm and hold its shape. Drain carefully, spread onto a greased tray and set aside to cool slightly.
Beat the ricotta, pecorino and egg yolks together until well combined. Stir in ½ cup Broccolini® pesto. Spoon into the pasta shells.
Preheat the oven to 180°C fan-forced. Spoon the tomato sauce into the base of an 8-cup capacity lightly greased baking dish. Poke the pasta shells into the sauce. Cover tightly with foil and bake for 15 minutes. Increase the oven to 220°C fan-forced, remove the foil and sprinkle over the mozzarella. Bake uncovered for 8-10 minutes, or until lightly golden on top. Spoon over some of the remaining pesto. Serve.