Preparation Bring a 6-quart pot of salted water to a boil. Add frozen broccoli, haricots verts, and edamame and cook, uncovered, until crisp-tender, about 3 minutes. Transfer vegetables with a slotted spoon to a large bowl. Add pasta to boiling water and cook until al dente, then drain in a colander. Meanwhile, heat 2 tablespoons oil in a deep 12-inch skillet over high heat until hot but not smoking and sauté garlic and red pepper flakes, stirring, until garlic is golden, about 1 minute. Transfer oil with garlic and red pepper to a cup. Add remaining 2 tablespoons oil to skillet and cook onions, stirring, until softened and pale golden, about 3 minutes. Add boiled vegetables and tomatoes and cook, covered, until vegetables are tender, about 5 minutes. Add butter and cheese and stir until combined. Put fettuccine in a deep serving dish and toss with vegetable mixture and garlic oil.
Preparation Bring a 6-quart pot of salted water to a boil. Add frozen broccoli, haricots verts, and edamame and cook, uncovered, until crisp-tender, about 3 minutes. Transfer vegetables with a slotted spoon to a large bowl. Add pasta to boiling water and cook until al dente, then drain in a colander. Meanwhile, heat 2 tablespoons oil in a deep 12-inch skillet over high heat until hot but not smoking and sauté garlic and red pepper flakes, stirring, until garlic is golden, about 1 minute. Transfer oil with garlic and red pepper to a cup. Add remaining 2 tablespoons oil to skillet and cook onions, stirring, until softened and pale golden, about 3 minutes. Add boiled vegetables and tomatoes and cook, covered, until vegetables are tender, about 5 minutes. Add butter and cheese and stir until combined. Put fettuccine in a deep serving dish and toss with vegetable mixture and garlic oil.