Just a quick update
Bought Tesco Cornish Vanilla Custard in the end. It's a very light vanilla colour and in the soft light of our dining room didn't look a lot different from white sauce. No-one noticed - my Dad had extra helpings and my Mum complimented me on how lovely tasty and creamy it was. Was very tempted to just bask in the praise but being a good honest daughter had to come clean.
Have another pot in the fridge ready for New Years Day and mince pies
Happy New Year to you all - hope it's cool one (if you get my drift) x