If bitter isn’t quite to your taste, then blanch the cleaned and trimmed broccoli rabe in salted boiling water for about a minute to lower its intensity. However, if you have a palate for bitterness, no need to blanch.
Rapini can be blanched a few days before you’re ready to use it, especially if it’s about to spoil. Blanched rapini will stay good in the fridge for up to five days. You can make a quick side with the blanched rapini by sautéing it, or try adding it to a grilled cheese sandwich, calzone, pasta, pizza, or a breakfast frittata.