Preparation Whisk together oil, crème fraîche, vinegar, sugar (if using), 1 teaspoon salt, and 1/2 teaspoon pepper in a large bowl. Coarsely chop tomatoes and toss with shallot and dressing. Marinate until ready to use, at least 10 minutes. While tomatoes stand, cook fusilli in a pasta pot of well-salted boiling water until al dente. Drain in a colander and immediately add to tomato mixture, tossing to combine. Cool to warm or room temperature (do not chill), tossing occasionally, then stir in herbs.
Preparation Whisk together oil, crème fraîche, vinegar, sugar (if using), 1 teaspoon salt, and 1/2 teaspoon pepper in a large bowl. Coarsely chop tomatoes and toss with shallot and dressing. Marinate until ready to use, at least 10 minutes. While tomatoes stand, cook fusilli in a pasta pot of well-salted boiling water until al dente. Drain in a colander and immediately add to tomato mixture, tossing to combine. Cool to warm or room temperature (do not chill), tossing occasionally, then stir in herbs.