Heat a splash of olive oil in a large skillet over medium heat. Add the finely diced onion and sauté for about 5-7 minutes, or until golden brown. Stir in the minced garlic and cook for an additional 30 seconds until fragrant.

Increase the heat slightly and add the ground beef. Brown the meat for about 5-7 minutes until fully cooked.

Stir in the tomato puree, cooking for about 1 minute. Pour in the red wine and let it simmer and reduce by half, around 3 minutes.

Add the tomato passata, beef stock, Worcestershire sauce, chopped basil, oregano, and sugar. Stir well and let it simmer for 25 minutes.

Preheat your oven to 180°C (350°F). Cut off the tops of the crusty rolls and hollow out the insides.

In a small bowl, mix together the melted butter, garlic paste, grated parmesan, and optional parsley. Coat the inside and outside of each roll with the garlic butter.

Cook the spaghetti according to package instructions, then drain and toss with the bolognese sauce.

Fill each hollowed bread bowl with the pasta and bolognese mixture. Top with shredded mozzarella cheese.

Place the filled bowls on a baking tray and bake for 8-10 minutes until the rolls are golden brown and crispy.

Let the pasta-filled bread bowls cool for a few minutes before serving.