1. Peel and finely slice the onion and carrot.
2. In a large saucepan, heat a little olive oil and sauté the onion until translucent. Then add the carrot and a splash of water to prevent sticking, continue cooking for 10 minutes.
3. Add the ground meat, continue cooking for 5 minutes while stirring.
4. Pour in the sauce, spices, salt, and pepper, and let simmer for 30 minutes on low heat.
5. Meanwhile, cook the pasta in a pot of salted boiling water following the instructions on the packaging, then drain well.
6. Preheat the oven to 180°C (350°F).
7. Prepare a light béchamel sauce by dissolving the cornstarch in a little milk and pouring it into a small saucepan. Heat until boiling, stirring constantly until the mixture thickens. Season to taste, then remove from heat.
8. Mix the pasta with the Bolognese sauce, then pour into a gratin dish. Pour the béchamel sauce over the top and sprinkle with grated cheese.
9. Bake for 20 to 30 minutes, until the cheese is nicely browned.