Prepare and slice the leeks. Peel and finely grate (shred) the carrots. Pour the oil into a frying pan and add the leeks and carrots. Stir well and fry gently for 7-8 minutes to soften the vegetables. Slowly add the breadcrumbs, stirring all the time, then add the chopped parsley and a little salt and freshly-ground pepper.
Crack the egg into a dish or bowl and beat well. Allow the mixture in the pan to cool a little then add the beaten egg and stir well. Use the butter to grease a small baking tin and press the vegetable mixture well into the tin. Cover with aluminium foil and cook in a preheated oven at Mk 4 - 350ºF - 180ºC for 40 minutes.
Remove the tin from the oven, take away the foil and use a knife around the sides to loosen the loaf. Turn the tin upside-down onto a plate and the Baked Leek and Carrot Loaf should fall easily from the tin.