Cook gnocchi in a pot filled with plenty of boiling salted water. As soon as gnocchi has risen to surface of the boiling water, rinse under cold water and drain well. Toss in a little oil to prevent sticking.
To make filling, heat oil in a large frying pan. Add onion, garlic, zucchini, carrot and bay leaves, cook, stirring, for 2 minutes or until softened. Add mince, cook until browned all over. Stir in flour, tomato paste and then Worcestershire sauce until well combined. Gradually stir in stock, bring to boil and then cook over a med-high heat, uncovered for 5 minutes or until thickened. Season with salt and pepper.
Spoon into an oven-proof dish (approximately 300ml capacity). Top with gnocchi and cheese.
Cook for 15 minutes or until cheese has melted and mixture is bubbling.