Reduce the heat to low. Add 2 tablespoons grated bottarga. Stir and simmer for a few minutes adding a little more olive oil if necessary. Add a ladle of pasta cooking water to create an emulsion.
Drain the pasta.
Mix the pasta in the pan, and add the rest of the bottarga.
Stir for 1 minute, then add the remaining parsley and the juice of half a lemon.