NOTE: Use good quality fresh or frozen tortellini. Break the broccoli into florets and slice the tender stems. Peel and cut the carrots diagonally into 1/4-inch slices. Rinse, dry and cut the white part and 2 inches of the green into thin julienne. Core, seed and cut into julienne strips the red and yeller peppers. Cook the tortellini in boiling salted water according to package instructions. Drain thoroughly and place in a large mixing bowl. Cook the broccoli florets, stems and carrots separately in boiling salted water just until tender. Drain and combine with the tortellini. Blanch the julienned leeks 1 minutes in boiling water; drain. Add the leeks, red and yellow peppers, and fresh basil to the salad and toss to combine. Process the egg yolk, lemon juice, mustard and vinegar in a food processor for 30 seconds. With the machine running, pour the oils in a thin steady stream through the feed tube to make a light mayonnaise. Add the thyme, orange zest and salt and pepper to taste. Process to combine. Pour the dressing over the salad and toss to coat thoroughly. Serve at room temperature or slightly chilled.