Bring a large pot of salted water to a boil. Cook the farfalle according to package directions until al dente. Scoop out 1/2 cup of pasta water before draining, then drain the pasta and set it aside.

While the pasta cooks, heat the olive oil and butter together in a large skillet over medium-high heat. Once the butter melts and the foam settles, add the zucchini pieces. Spread them in a single layer and let them cook undisturbed for 2 minutes so they get some color on the bottom. Give them a stir and cook another minute.

Add the asparagus pieces to the skillet. Stir everything together and cook for 2 to 3 minutes until the asparagus is bright green and just barely tender when you press a piece with a fingernail. It should still have a little resistance. Add the minced garlic and stir for about 30 seconds until it smells fragrant.

Pour in the chicken broth and heavy cream. Stir to combine and let the mixture come to a gentle simmer. Add the frozen peas directly to the pan. They will thaw in about 60 seconds in the warm liquid. Season with the salt, pepper, and red pepper flakes if using.

Add the drained pasta to the skillet and toss with tongs to coat it in the sauce. Sprinkle the Parmesan over the top and toss again. The cheese will melt into the sauce and thicken it slightly. If it looks too thick, stir in a splash of the reserved pasta water. If it looks thin, let it cook over medium heat for another minute or two, tossing often, until it clings to the pasta.

Taste and adjust the salt and pepper. Stir in the lemon zest if using. Serve right away in warm bowls with extra Parmesan on the side.