Preheat oven to 450. Lightly grease a 9x9 baking pan.
Medium dice the yellow onion and set aside. Roughly chop bacon into bite-sized pieces.
Heat a large pot over medium heat. Cook bacon for 5-10 minutes, or until crispy. Cook your bacon a little crispier than you normally would, as it will soften over the rest of the cooking process.
Add onions to the pot and cook for another 7 or so minutes, until translucent. Stir often to scrape up any browned bits.
Add milk and chicken broth to the pot and stir. Bring to a boil.
Lower the heat to simmer and whisk in yellow cornmeal and garlic powder. Pour the cornmeal slowly and evenly, and use a whisk to prevent clumping. Cook for 20 minutes, stirring often.
Tear the spinach leaves from the stems and stir them into the pot along with the greek yogurt. Cook for another 5 minutes, stirring occasionally.
Remove from heat. Add salt and pepper to taste (I almost never need to add salt at this point). Stir in eggs.
Pour the mixture evenly into the greased baking pan. Sprinkle the top with cheese. Cover with aluminum foil.
Bake for 20-25 minutes covered; remove foil and bake for another 5 minutes uncovered. Divide into 4 portions and serve.