Bring a large pot of water to a boil, salt it, add the pasta and cook until al dente. Drain.
While the pasta is working, in a large skillet, heat the EVOO, 4 turns of the pan, over medium heat. Add the shallots and garlic and cook for 5 minutes. Add the carrots and zucchini and cook for 5 minutes. Season to taste with salt and pepper. Stir in the citrus juices and peels and heat through. Add the butter and stir until melted. Remove from the heat. Add the spaghetti, parsley, mint and thyme and toss to combine. Top with the radicchio.