Cook the meatballs through, then roughly chop. Set aside.

Cook pasta according to packet instructions. Add the beans once the water is boiling then for the final 5 minutes add the peas and leek. Drain well.

Preheat grill to medium-high

In a small saucepan whisk the quark, sugar alternative, stock, onion granules, garlic, chives, mustard, and 3/4 of the cheese. Heat gently until the mixture is smooth. Season with salt and pepper.

Transfer pasta and vegetables to an oven proof ceramic tray.

Pour in the cheese sauce and meatballs and stir until combined with the pasta.

Sprinkle the top with the remaining cheese and breadcrumbs.

Grill for 5-6 minutes until the cheese has melted.