Bring a large pot of salted water to a boil. Cook the pasta until al dente according to package directions. Reserve 1 cup of pasta water before draining.
Meanwhile, heat olive oil in a large skillet over medium heat.
Add the sliced leek and asparagus. Cook for 3–4 minutes until slightly softened.
Stir in the snap peas and garlic. Season with salt, pepper, and chili flakes.
Add the peas and continue cooking until the vegetables are bright green and tender-crisp.
Add the cooked pasta to the skillet along with the lemon zest, grated Pecorino, and a splash of reserved pasta water.
Toss until the cheese melts into a silky sauce.
Stir in the cream and two-thirds of the fresh herbs. Add more cream or pasta water if needed for a smooth consistency.
Taste and adjust seasoning.
Serve the Easy Pasta Primavera Recipe immediately with extra cheese, fresh herbs, and additional lemon zest.