In a pan, heat the olive oil over medium heat, add the onion and stir fry until translucent. Add in the garlic and fry for another minute or so. Mix in the passata, sugar, salt and black pepper. Let it simmer until thickened, about 10-15 minutes. Set aside.
To make the meatballs, place the mince, spice blend, egg and panko breadcrumbs in a large bowl. Combine the ingredients with a fork, careful not to compress the mixture.
Shape the meatballs with your hands, working them only until they are just formed. TIP: wet your hands with water before forming the meatballs to prevent the mixture from sticking to your hands.
Preheat your oven to grill mode.
Heat a heavy-based pan to medium heat. Add the olive oil to the pan, enough to cover the base. Once hot, add the meatballs, leaving space in between them.
Sear on both sides, then reduce the heat to low and fry for approximately 10 minutes or until meatballs are cooked through and browned.
Lightly toast your bread in the oven. Gently spoon the meatballs into the toasted bun, drizzling some sauce over the top. Add a good melting cheese like provolone or mozzarella, then grill in the oven to melt.
