Prepare Pasta & Sauce according to stovetop directions on pack. Cool slightly

Heat oil in a large, non-stick frying pan over a medium heat. Add leek and cook, stirring occasionally, until soft. Add mushrooms and cook, stirring for 2 minutes, or until soft. Remove from heat. Cool slightly

Whisk eggs and mustard in a large bowl until combined. Add cooked Pasta & Sauce, leek and mushroom mixture and half the parmesan. Season with salt and pepper. Stir to combine

Pour into a greased ovenproof dish (6-cup capacity). Sprinkle with remaining parmesan

Cook in a moderate oven (180°C) for about 30 minutes, or until golden brown and set. Stand for 15 minutes

Slice and serve with salad leaves