Begin by bringing a large pot of well-salted water to a rolling boil over high heat.

While the water is boiling, cut fresh broccoli into bite-sized florets and slice stems into thin rounds.

Once boiling, add shell pasta and cook according to package instructions until al dente, about 9-11 minutes.

Three to four minutes before pasta is done, add the broccoli to the boiling water to blanch it.

After the broccoli has blanched, reserve 1-1.5 cups of the pasta water and drain pasta and broccoli together.

In a large skillet, heat olive oil over medium-low heat, then add minced garlic and red pepper flakes until fragrant.

Pour in broth and add lemon zest, simmer for 2-3 minutes; add lemon juice off the heat.

Add drained pasta and broccoli to the skillet, tossing to coat with the sauce.

Sprinkle in Parmesan cheese or nutritional yeast, stirring until melted and fully incorporated.

Gradually stir in reserved pasta water until desired sauce consistency is reached.

Mix in any optional ingredients, adjusting seasoning as needed, and serve hot garnished with fresh herbs.