Line a sheet pan with aluminum foil or parchment paper.
Rinse broccoli rabe, cut off the very bottom of each stalk, then cut the stems into 1-2 inch chunks. Leaves and florets can be left whole.
Toss the broccoli rabe with the olive oil, salt, and red pepper flakes in a large bowl, then spread out into one layer on sheet pan.
Roast broccoli rabe for 15 minutes, or until stems are tender and leaves are crispy.
Notes
Storage Tips: You can store leftover roasted broccoli rabe in an airtight container in the refrigerator for up to 3 days. But note that the leaves will loose their crispness in the fridge. Put them back in an air fryer or hot oven to re-crisp when reheating. Expert Tips: Depending on the size of your broccoli rabe bundle, you may want to spread out over 2 sheet pans instead of 1. Keeping the broccoli rabe in one thin layer ensures that it roasts rather than steams, so you get crispy leaves and lightly browned stems and florets.You might wonder whether you can roast the broccoli rabe stalks whole, rather than cutting them into bite-sized chunks. You certainly can, though the fibrous stems are harder to cut once the rapini is roasted. Chopping it in advance means you can just pop the pieces in your mouth once they're on your plate.