In a large saucepan with plenty of boiling water add the bouillon cubes. Once dissolved, add the pasta and cook following pack instructions. Just before draining the pasta, take ½ cup of pasta water and set aside.
While pasta is cooking, in a large bowl whisk the lemon zest, lemon juice, pecorino, olive oil, salt and pepper until combined, then add the pasta water and whisk again. Add the drained pasta in the bowl and mix. Serve hot with some more grated pecorino and fresh rocket leaves.