Cauliflower Cheese

1 cauliflower
1.5 oz. butter
2 tablespoons flour 1 onion
2 egg yolks
2 tomatoes 1/2 pint milk
4 oz. lean ham
salt and pepper 1 teaspoon freshly made English mustard
4 oz. grated Cheddar cheese
pinch of cayenne

Steam the cauliflower until tender (or cook it in a little boiling salted water and drain well). Cool and divide into florets. Peel and very finely chop the onion. Chop the ham. Peel the tomatoes. Melt the butter in a saucepan, add the onion and cook over a low heat until the onion is soft and transparent. Add the flour and mix well. Gradually blend in the milk, stirring continuously over a medium heat until the sauce is thick and smooth. Add half the cheese and continue to stir until the cheese has melted. Lower the heat and beat the egg yolks into the sauce. Do not boil. Season with salt, pepper and a pinch of cayenne, lightly fold in the cauliflower, tomatoes and ham and transfer to a fireproof serving dish. Sprinkle over the remaining cheese and cook in a moderate oven (350°F, Reg. 4) for 15-20 minutes until the dish is hot through and the top is golden brown.