Classic Pasta Primavera

To peel the tomatoes, dunk the cored tomatoes in a pot of boiling water until the skins split and begin to curl around the cored area, about 15 to 30 seconds; transfer the tomatoes to a bowl of ice water, then peel off the skins with your fingers.

1. Bring 4 quarts water to boil in large pot for pasta. Bring 3 quarts water to boil in large saucepan for vegetables; add 1 tablespoon salt. Fill large bowl with ice water; set aside. Add green beans to boiling water in saucepan and cook for 1-1⁄2 minutes. Add asparagus and cook for 30 seconds. Add zucchini and cook for 30 seconds. Add peas and cook for 30 seconds. Drain vegetables and immediately plunge them into prepared ice water bath to stop cooking. Let vegetables sit until chilled, about 3 minutes. Drain well and set aside.
2. Melt 3 tablespoons butter in now-empty saucepan over medium heat. Add mushrooms and cook until softened and lightly browned, 8 to 10 minutes. Stir in tomatoes and pepper flakes, if using, and cook until tomatoes begin to lose their shape, about 7 minutes. Stir in heavy cream, bring to simmer, and cook until sauce is slightly thickened, about 4 minutes; cover to keep warm and set aside.
3. Add pasta and 1 tablespoon salt to pot and cook, stirring often, until al dente. While pasta is cooking, melt remaining 3 tablespoons butter in 12-inch skillet over medium heat. Add garlic and cook until fragrant, about 30 seconds. Add blanched vegetables and cook until heated through and infused with garlic flavor, about 2 minutes. Season with salt to taste. Meanwhile, bring tomato sauce back to simmer over medium heat.
4. Drain pasta and return it to pot. Add tomato sauce, vegetables, basil, and lemon juice to pasta and toss to combine. Season with salt to taste and serve immediately, passing Parmesan separately.