Have you tried Black Farmer eggs from Ocado. They are amazing and every bit as yellow!Definite thumbs up for those eggs. Provenance? To get eggs with yolk that dark in the UK you need a specialist producer, using traditional breeds such as Marans or Legbars. Even premium free range eggs from the supermarkets are pale and insipid by comparison.
https://www.ocado.com/webshop/produ...ram=eggs&parentContainer=SEARCHeggs_SHELFVIEW