Bring a large pot of water to the boil over high heat.
Roughly break the broccoli into florets and chop the stems. Add to the boiling water and boil for 2-3 minutes. Use a slotted spoon to remove the broccoli from the water and onto a clean kitchen towel. Allow the broccoli to cool slightly.
Generously salt the same water, and add the orecchiette. Stir to break up the pasta, and then cook until al dente, about 12 minutes.
While the pasta is cooking, heat the olive oil over medium heat in a large heavy-bottomed skillet.
Add the garlic, and cook gently until fragrant, careful to not let the garlic brown.
Squeeze the water from the broccoli and transfer to a cutting board. Chop the florets and stems into small pieces, and then transfer into the pan with the garlic. Add the lemon zest and red pepper flakes.
When the pasta is done, use a slotted spoon to transfer it directly into the pan with the broccoli, adding a little pasta water as you do so.
Toss well, add a squeeze of lemon juice and some salt and pepper. If needed, add a bit of extra pasta water to thin it out.
Serve with freshly grated parmesan and wedges of lemon to squeeze over top.