How to Make It
Preheat the oven to 400°F. Place the baguette slices on a baking sheet; brush with the oil and top each with 2 pieces of the mozzarella. Bake until the cheese is bubbly and light golden brown, about 12 minutes.
Meanwhile, heat a large ovenproof nonstick skillet over medium-high. Add the sausage and cook, stirring and breaking it apart with a wooden spoon, until almost cooked through, 5 minutes. Add the onion and garlic and cook, stirring, until the onion is translucent, about 3 minutes. Stir in the tomatoes, oregano, and salt. Bring to a simmer and cook, stirring occasionally, until slightly thickened, about 3 minutes.
Reduce oven temperature to 375°F.
Break the eggs into the sauce, leaving space between them. Sprinkle with the pepper. Transfer to oven and bake until the whites are set and the yolks are still soft, 7 to 9 minutes. Top with oregano. Serve in bowls with the mozzarella toast.