Preheat oven to 400F.
Lightly grease a 9x9 baking dish and set aside.
Prepare orzo according to the directions on the package.
Cook the chopped bacon in a large skillet until it begins to brown; add onions and continue to cook for 3 to 4 minutes, or until onions are soft and bacon is cooked through.
Stir in the spinach and cook for 2 minutes, or until wilted.
Drain and rinse the orzo pasta; add it to the skillet.
Remove from heat and stir until well combined; transfer to previously prepared baking dish and set aside.
In a medium sized mixing bowl combine feta, eggs, milk, salt and pepper; whisk until thoroughly incorporated.
Pour the milk mixture over the orzo mixture.
Bake for 20 to 25 minutes, or until eggs are set and top is lightly browned.
Let stand for 10 minutes.
Serve with yogurt.