"Raspberry vinegar, maple syrup, Dijon mustard, and tarragon make up this dressing from a popular Florida restaurant. Serve with Martha's Vineyard Salad or your favorite greens. Make the dressing at least 3 hours in advance and refrigerate to meld flavors. Can make up to 1 week in advance."
Make the dressing several hours ahead to mingle the flavors. It will keep for a week refrigerated.
In a nonreactive large mixing bowl, whisk raspberry vinegar, olive oil, vegetable oil, maple syrup, Dijon mustard, tarragon, and salt together vigorously. It should form a loose emulsion. Refrigerate until ready to use. Whisk again before using.