The greengrocer used to cook them daily and you were always able to buy a fresh one. It seems they are only available now in pre-packs which are not at all same. I buy a bunch of raw ones regularly and cook them for 20 minutes in the pressure cooker. I’m yet to make a beetroot cake.
Ingredients for Jellied Beetroot: 1lb cooked beetroot, cubed One packet of blackcurrant, cherry or raspberry jelly ½ pint boiling water to melt jelly ¼ pint vinegar 2 tbsps lemon juice Cold water to make jelly up to a pint Method for Jellied Beetroot: Pack jars with beetroot and pour jelly over. Shake jars to ensure no air spaces and further top up if needed. Easy Peasy!
I mentioned beetroot jelly Minimoon but I didn't have the recipe so great that you have posted it. We had it at a village garden open day lunch anf dh loved it.(I hate beetroot).