Preheat the oven to 200C/180C Fan/Gas 6.
Heat the oil and butter in an ovenproof, lidded saucepan over a medium heat. When the butter is foaming, add the shallots, leek, celery and garlic and fry for 2-3 minutes, stirring well, until softened but not coloured.
Add the rice and continue to cook, stirring well, for a 1 minute.
Pour in the stock, then add the bay leaves, saffron and curry powder and heat until simmering.
Add the leftover cooked meats, return the mixture to a simmer, then cover the pan with the lid.
Transfer the pan to the oven and cook for 12-15 minutes, until the rice is tender.
Meanwhile, carefully lower the eggs into a pan of simmering water and cook for 6 minutes. Drain well and run the eggs under a cold running tap. Peel the eggs and cut them into quarters lengthways.
When the kedgeree is cooked, stir through the parsley and sage, then fold in the egg quarters. Season with salt and pepper.
To serve, take the pan to the table and spoon it into bowls. Garnish with a lemon wedge and serve with bread and butter, if desired.