Combine ingredients for Maple-Dijon Vinaigrette in a jar with a tight fitting lid or bowl then shake or whisk to combine and refrigerate. Can be made up to 5 days ahead of time.
Heat extra virgin olive oil in a large skillet over medium heat. Add onions then cook until soft and caramelized, 40-50 minutes, stirring occasionally. Turn heat down slightly if they begin to sear or burn. Season with salt then set aside. Can be made up to 3 days ahead of time then added to the salad either warm or cold.
Add spring mix to a large serving bowl then top with caramelized onions, cheese, apples, and granola. Drizzle with Maple-Dijon Vinaigrette then toss to coat and serve.
Notes
Estimate nutritional information includes entire vinaigrette recipe.