Step 1

Mix the mushroom ketchup and Worcestershire sauce with ½ pint (275 ml) water and put to one side. Heat the oil in a medium-sized saucepan then add the onion and carrot and cook them together for about 8 minutes until they have softened and browned slightly at the edges.

Step 2

Then, using a draining spoon, remove them to a plate. Now turn the heat up to high and brown the meat quickly in the pan, stirring it around until it too becomes brown and toasted at the edges.

Step 3

Drain off the fat that has come out of it, then sprinkle in the mixed herbs and a seasoning of salt and pepper and return the carrot and onion to the pan.

Step 4

Next stir in the flour and then gradually add the mushroom ketchup and Worcestershire sauce mixture, stirring as you do so.

Step 5

Turn the heat down to the gentlest possible simmer, cover the pan and simmer for 30 minutes.

Step 6

Meanwhile, cut the potatoes into chunks and boil them in salted water until tender, then drain them and return them to the pan.

Step 7

Add the yoghurt and butter, them mash them to a smooth purée.

Step 8

Then preheat the grill.

Step 9

When the meat is cooked, taste to check the seasoning and transfer one half-quantity, for Spaghetti with Mexican Sauce, to a bowl to cool, see introduction, and related recipe below.

Step 10

Put the rest of the meat into a 5 inch (13 cm) ramekin or small pie dish. Then spoon the mashed potato mixture all over the top, levelling it off with a fork.

Step 11

Now combine the grated cheese with the herbs, and sprinkle this mixture all over the surface of the potato.

Step 12

Place the dish under the grill till the cheese is brown and bubbling.