1/2 cup chopped sun-dried tomatoes with no liquid (reconstituted according to package directions, if necessary)
1/2 cup chopped onion
1 clove garlic, minced
1 tablespoon olive oil
1/4 teaspoon kosher or sea salt
1/4 teaspoon black pepper
Preheat oven to 375 degrees.
For the quiche filling:
Heat onion and garlic in a skillet with olive oil for about 5 minutes, until onion is softened and translucent. Add spinach and cook, just until wilted. Remove from heat. Mix in sun-dried tomatoes.
Meanwhile, beat/whisk egg whites until very frothy. Whisk whole eggs in a separate bowl. Combine the eggs and whites. Add parmesan cheese, salt, and pepper. Fold in the spinach tomato mixture and pour into the pie shell. Bake for 25 minutes or until set in the center and golden at the edges.
If desired, sprinkle with walnut pieces 5 minutes before removing from the oven.