Spinach Onion Feta quiche

I got this recipe from Sparkpeople; made a couple changes to adapt to my taste.

1/2 medium onion, diced (about 1/2 cup chopped is what I ended up with)
6-oz fresh baby spinach
2 large eggs
1/2 cup all purpose flour
1/2 tsp baking powder
1/4 tsp salt
pinch cayenne pepper
1 1/3 cups non fat milk
1/2 cup reduced fat feta cheese

Preheat oven to 400F.
Lightly grease a 10-inch quiche/tart pan (or a pie plate) *(I actually used a glass brownie sized baking dish)
In a medium frying pan, cook diced onion with a bit of vegetable oil (or cooking spray) over medium-high heat until translucent and tender. Add in fresh spinach and cook until just wilted. Set aside to cool for a few minutes
In a large mixing bowl, whisk together eggs, flour, baking powder and salt. Whisk in milk, then stir in spinach-onion mixture.
Pour quiche base into prepared pan. Top with feta cheese.
Bake for 25 minutes, or until center is set and the outside edge is golden brown.
Let set for 5 minutes, then slice and serve.

Original recipe said this made 6 servings. I actually put the ingredients into my Recipes and made it 4 servings and got these nutritional values:

Per Serving: 168 calories, 19 carbs, 5 gm Fat

Number of servings 4

Ingredients Calories Carbs Fat
Produce - White Onion Chopped (Correct) , 0.5 Cup chopped 34 8 0
Northeast - Baby Spinach , 5 1/2 cup 40 6 0
Eggs - Whole Cal, 2 large 140 0 10
Great Value - All Purpose Flour, 1/2 cup 220 44 0
Borden - Viva - Skim Delight (Fat Free Milk), 1.3 cup 117 17 0
Athenos - Reduced Fat Feta Cheese- Crumbled, 0.5 cup 120 2 8
Add Ingredient
Total: 671 77 18
Per Serving: 168 19 5