The tanginess of Humboldt Fog gives additional flavor to this elegant salad. Feel free to substitute other stone fruit like peaches or nectarines for the plums.
In a large serving bowl, whisk together vinegar, salt, and pepper. Gradually whisk in oil until vinaigrette thickens. Add spinach, plums, cheese, shallots, and almonds and toss gently until evenly coated.