Boil salty water and prepare pasta al dente according to the directions on the bag -- making sure to reserve at least 1 cup pasta water.
In a large pan over medium-high heat, sautee 1 diced onion in olive oil with a pinch of salt and a pinch of red pepper flakes.
Let this mixture cook for a few minutes until the onions begin to get translucent and soft.
Once they have a little color on them, add the shaved broccoli and a little more salt.
Cook the broccoli down for 2 minutes, then add some salty butter to it and stir.
Once the broccoli has softened, add the 2 boursin cheeses and about ¾ cup of water.
Stir everything up so that the boursin melts into the pasta water. If the mixture looks too thick, add ¼ cup more pasta water to loosen it.
Now add your pasta to the sauce pan once its al dente -- do it straight from pot so that the excess pasta water gets in there!
Let the noodles finish cooking in the sauce over low heat for 1-2 minutes.
Finish with a squeeze of lemon juice and some red pepper flakes and enjoy!