Heat the oil in a medium-deep frypan over high heat. Cook the onion, carrot, rosemary and Italian seasoning, stirring occasionally, for 4 mins or until the onion is softened. Add the pork mince and cook, stirring occasionally, for 3 mins, or until the mince is browned. Then add the courgette, stock and tomatoes, stir to combine and bring to a simmer. Reduce the heat to low and cook, stirring occasionally, for 10 mins, or until slightly thickened.