Heat up water in a saucepan and cook the broccoli for 5 minutes.
Bring the water to the boil with a little bit of salt. Add the pasta and cook al dente.
Cut the hazelnuts in pieces and roast them in a pan till golden brown.
In a blender, blend the broccoli, feta, roasted hazelnuts, garlic, basil, olive oil, shallot and pasta water till smooth.
Add the sauce to the pasta.
In a bowl, mix together the lemon zest, feta and basil. Sprinkle it on top when serving together with the extra roasted hazelnuts.