Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper or lightly grease it with olive oil or cooking spray.
Place the English muffin halves, cut side up, on the baking sheet.
In a small bowl, beat the eggs and season with a pinch of salt and pepper.
In a skillet over medium heat, sauté the diced onion and bell pepper until soft, about 3-4 minutes. Add the cooked crumbled sausage and mix.
Distribute the sautéed mixture evenly among the English muffin halves.
Pour the beaten eggs over the sautéed mixture on each English muffin half, filling each until just covered.
Sprinkle shredded mozzarella cheese over the egg mixture on each muffin.
Sprinkle dried oregano over the top, adding extra salt and pepper if desired.
Bake in the preheated oven for about 10 minutes or until the cheese has melted and the eggs are set.
Remove from the oven, let cool slightly, then serve warm and enjoy!