1. Bring a large pot of salted water to a boil and cook the broccoli florets until very tender, about 5–7 minutes.

2. Using a slotted spoon, transfer the broccoli to a large bowl, keeping the pot of water on the heat for the pasta.

3. Add the pasta to the same boiling water and cook according to package directions until al dente, reserving about 1 1/2 cups of the starchy pasta water before draining.

4. While the pasta cooks, smash the warm broccoli in the bowl with a potato masher or the back of a spoon until it forms a chunky, spreadable mixture with small pieces remaining.

5. Season the smashed broccoli with 1/2 teaspoon of salt, 1/4 teaspoon of black pepper, and the lemon zest, then drizzle in 1 tablespoon of olive oil and stir to combine.

6. In a large skillet, heat the remaining olive oil and the butter over medium heat until the butter is melted and foamy.

7. Add the minced garlic and red pepper flakes to the skillet and cook, stirring constantly, for 30–60 seconds, just until fragrant.

8. Stir the smashed broccoli into the skillet and add a splash of reserved pasta water, stirring to loosen it into a thick, saucy consistency.

9. Add the hot, drained pasta to the skillet and toss with the smashed broccoli mixture over low heat, adding more reserved pasta water a little at a time as needed to coat the pasta.

10. Sprinkle in the grated parmesan cheese in two or three additions, tossing well after each addition until it melts into a glossy, creamy sauce.

11. Stir in the lemon juice, taste, and adjust seasoning with more salt, pepper, or red pepper flakes to your liking.

12. Remove from the heat and toss in the chopped fresh parsley, adding another drizzle of olive oil if the pasta looks dry.

13. Serve the smashed broccoli pasta in warm bowls, topped with toasted breadcrumbs and extra parmesan cheese if desired.