Toss together spinach, mandarin slices, and almonds.
Whisk together the vinaigrette ingredients. Add as much dressing as you'd like to the salad, and toss. Store any leftover dressing in the fridge, and use within a month.
Serve salad immediately.
Make Ahead: Toss together all the salad ingredients up to 2-3 days ahead of time. Add the dressing immediately before serving.