I added the garlic and onion to this recipe as a matter of personal preference. I used dried/instant that comes in the spice section of the store, you can obviously use fresh if you like. After I baked these, I kept them on my electric serving tray, on low heat, to keep them warm and crisp.
Preheat oven to 350 degrees. Place frozen shells onto cookie sheet. Combine eggs, feta cheese, artichokes, garlic & onion in a mixing bowl, whisking well to blend. Spoon into shells and bake 20 minutes uncovered. Remove and serve.