I saw a British magazine and was really suprised that their article on plum
pudding, never had any suet in them at all. All the recipes seems to have
margarine or butter in them.
Here is a great sauce.

CREAMY RUM SAUCE
Serving Size : 8

1/2 c. sugar
2 Tbsp. cornstarch
1/4 tsp. salt
1 1/2 c. milk (see note)
1/4 c. butter
1/8 tsp. nutmeg
1/2 c. rum

In a three litre microwave safe bowl, mix sugar, cornstarch and salt. (needs a large bowl, because it will bubble up). Gradually stir in milk and butter. Micro on full for about 3 min. or until thick and creamy. Stirring after each min. Stir in the spice and rum and pour into a sauceboat, so sauce is ready to reheat at serving time. Makes 2 cups. NOTE: For a creamier sauce, sub. 1/2 c. of canned evaported milk for 1/2 c. of the regular milk. (tastes great!)

NOTES : Perfect for over Christmas Pudding, and is made easily in the microwave.