Cauliflower and Broccoli in Tomato Sauce

1 onion, chopped fine
1 14-ounce can of chopped tomatoes, and their juices
3 tablespoons of tomato paste
3 tablespoons of flour
1 1/4 cups of milk
1 1/4 cups of water
3 cups of cauliflower florets
3 cups of broccoli florets
Salt and freshly ground black pepper to taste

Mix the onion, the tomatoes and their juices, and the tomato paste in a small saucepan.

Bring the mixture to the boil, lower the heat and simmer gently for 15 minutes.

Mix the flour with enough of the milk to form a paste.

Stir the paste into the tomato mixture, then gradually stir in the remaining milk and water.

Raise the heat and stir the mixture continuously until it boils and thickens.

Lower the heat. Season to taste with the salt and the pepper.

Keep the sauce hot.

Steam the cauliflower and the broccoli over boiling water for 5 to 7 minutes, or until the florets are just tender.

Transfer the vegetables to a dish, pout the hot sauce over them, sprinkle with some freshly ground black pepper.

Serve hot.