Steps
1. Cook the pasta according to package instructions until al dente. Drain and set aside.
2. In a skillet, heat the olive oil over medium heat. Add the chopped onion and sauté until translucent, about 3-4 minutes.
3. Add the diced tomato to the skillet and cook for an additional 2-3 minutes until softened. Season with salt and pepper.
4. In a separate pot, bring water to a gentle simmer. Crack the egg into a small bowl and gently slide it into the simmering water. Poach for about 3-4 minutes.
5. Combine the cooked pasta with the tomato and onion mixture, tossing to coat well.
6. Serve the pasta in a bowl, topped with the poached egg and garnish with fresh basil if desired.