Caramelized Onion, Spinach, and Shiitake Mushroom Pasta

Ingredients

*4 oz. whole wheat angel hair pasta or regular angel hair (equal to two servings of pasta)
*3 Tbsp. olive oil
*1 medium yellow onion, thinly sliced
*1/2 tsp. salt
*1 cup Shiitake mushrooms, chopped
*1 cup spinach
Freshly ground black pepper
Additional olive oil

Instructions

Cook pasta according to package instructions. Drain and keep warm until ready to use.
In a large skillet heat 2 Tbsp. of the olive oil over medium heat. Add the onions and salt and cook, stirring frequently, for 10 to 12 minutes, until onions begin to caramelize and turn deep golden brown.
Turn off heat. Add the mushrooms, spinach, and the remaining 1 Tbsp. olive oil. Stir for 2 to 3 minutes, until spinach begins to wilt and mushrooms are heated through.
Divide the pasta between two bowls. Top with the onion mixture. Drizzle with additional olive oil and freshly ground black pepper.

(source: http://www.espressoandcream.com/2010/07/caramelized-onion-spinach-and-shiitake.html)