In a small bowl, combine vinegar and shallot. Let mixture sit for at least 15 minutes.
Add lemon zest, lemon juice, cilantro, sugar, salt, and pepper. Whisking constantly, gradually add olive oil, a little at a time. Refrigerate for at least 2 hours before serving. If mixture separates, whisk to combine. Vinaigrette can be stored, refrigerated, in an airtight container for up to 3 days.
Recipe by Victoria at https://victoriamag.com/spring-crudites-lemon-cilantro-vinaigrette-recipe/