Halve the vanilla pod lengthways and scrape out the seeds. Mash the seeds with a little of the sugar so they separate.
Bring the water and rice to the boil in a heavy-based saucepan over a medium heat and let it simmer for about 5 minutes – or until the water has almost boiled away.
Add the whole milk, sugar, vanilla seeds and the vanilla pod, and bring the porridge to the boil, stirring. Once the porridge is boiling, turn the heat down low and put a lid on the pan.Leave the porridge over a low heat – at home I have it on 2 out of 9.
Let the porridge simmer very gently, covered, for about 40 minutes – stirring regularly as it cooks.Over a very low heat the porridge should not catch on the bottom, but still stir it carefully while it cooks.
For the last 5 minutes of the cooking time, remove the lid and cook the porridge until the rice is tender.Rice absorbs liquid differently from batch to batch, so keep an eye on it.
Fish out the vanilla pod and season the porridge with a pinch of salt if you like.Be aware that the porridge will be fairly loose while it is hot. It thickens as it cools, so do not cook it any further once the rice is tender.
Put the porridge in the fridge to chill, and if you can, leave it there overnight.
Risalamande
Pour boiling water over the almonds and leave them to soak for 10 minutes.Drain, slip the skins off the almonds and leave them to dry on a tea towel.
Roughly chop the almonds – remember to set aside a couple of whole almonds if it is for Christmas Eve.
Whip the cream to soft peaks.
Fold the whipped cream into the rice porridge together with the chopped almonds using gentle movements - do it in a couple of batches if you like.Do this gently so you don't knock the air out of the cream. It is a good idea to fold the cream in last.
Keep the risalamande in the fridge until it is to be served - then serve with warm cherry sauce and top with toasted slivered almonds if you like.