Hot Spinach and Artichoke Salad

1 tablespoon extra-virgin olive oil
1 (10 ounce) package spinach - rinsed, stemmed, and dried
1 red onion, thinly sliced
1 (8 ounce) jar marinated artichoke hearts
1 cup crumbled ff or low fat feta cheese

Directions:
Preheat oven to 300 degrees F (150 degrees C).
Drizzle olive oil on a rimmed baking sheet. Spread spinach leaves in a thick layer covering the baking sheet. Arrange onions and artichokes over the spinach, and drizzle the marinade from the jar over the entire salad. Sprinkle with the cheese (and sausage, if you wish).
Bake for about 10 minutes, or until the spinach is wilted but NOT crispy