Preheat your oven to 375°F. Grease a 9x13-inch baking dish with oil or cooking spray.
Heat a large skillet over medium heat and drizzle in the olive oil. Add the onion, diced sweet potato, smoked paprika, garlic, oregano, and a pinch of salt and pepper. Cook until the sweet potatoes are almost fork-tender, about 12–15 minutes.
Stir in the Italian sausage, breaking it up with a spoon. Cook until browned, about 5–7 minutes.
Add the spinach and cook just until wilted. Remove from heat.
In a separate bowl, whisk the eggs with a little salt and pepper.
Transfer the sausage–sweet potato mixture to the prepared baking dish. Pour the eggs evenly over the top, then sprinkle with fresh parsley.
Bake for 15–20 minutes, until the top is golden and the eggs are just set (internal temp should reach 160°F).