Mix the shallots and the vinegar in a bowl and marinate at room temperature for about 30 minutes to 1 hour.
Using a slotted spoon, take the shallots out and reserve them for later.
Add the onion powder, garlic powder, paprika and sugar to the vinegar, then add the olive oil in a thin stream and whisk well until the mixture emulsifies into a thick dressing.
In a larger bowl, combine the salad greens, peppers and reserved shallots, and dress with the dressing to your liking.
Place the salad in serving dishes and top with shaved provolone.
Shallot, Arugula & Spinach Salad
