This sunny pasta salad is a hit with kids and parents alike. Other fresh herbs, such as chopped dill or oregano, may be substituted for the tarragon.
In a large pot of salted boiling water, cook the pasta until tender, about 8 minutes. Drain it in a colander, rinse well, and drain again.
Meanwhile, in a large bowl, whisk together the vinegar, water, salt, sugar, tarragon, and pepper. Add the oil in a stream, whisking until well blended.
Add the pasta and the remaining ingredients to the bowl and toss well. Serve the salad at room temperature. Serves 8 to 10.