Heat the olive oil in a large, oven-safe skillet over medium heat.
Add the chopped onion and bell pepper. Cook until softened, about 5 to 7 minutes.
Stir in the minced garlic, cumin, smoked paprika, and chili powder. Cook for 1 minute until fragrant.
Pour in the crushed tomatoes and water. Season with salt and pepper. If using sausage, add it now. Bring the sauce to a simmer.
Reduce the heat to low, cover the skillet, and let the sauce cook for 10 minutes, allowing the flavors to meld.
Use a spoon to create four small wells in the sauce. Gently crack one egg into each well.
Cover the skillet again and cook for 5 to 8 minutes, or until the egg whites are set but the yolks are still runny. Alternatively, place the skillet under a preheated broiler for 1 to 2 minutes to set the tops of the eggs, watching closely.
Remove from heat. Sprinkle with feta cheese and fresh cilantro or parsley before serving.
Notes
You can prepare the tomato sauce base up to one day ahead. Store it covered in the refrigerator and reheat it gently before adding the eggs.
For a richer flavor, substitute half the water with vegetable or chicken broth.
Serve directly from the skillet with crusty bread for dipping.