Some people eat it in salads, the leaves that is. I've never done that, probably because it's best to pick them young and in May when they start to flower it can be pretty cold and therefore I am not in the mood to go on foraging trips.
The dandelion is a medicinal plant. There is a clue in the name. If a plant is called Something officinale it is a plant that is known for it's medicinal properties. Dandelion leaves are nutritious and a good diuretic. The root of the plant is considered a good detoxifier and a tonic for the liver. But that isn't what I was going to say at all. What this is all about is dying.
Dying isn't at all complicated. Most of the time you need about equal amounts of plant material to yarn (or whatever you want to dye). You put the plants into a pot with some water and simmer or boil it for about an hour and then strain it. This will work for most plants. Then you pour the dye solution into a pot and fill it up with water and put the yarn (or whatever) into the pot. This is then simmered for an hour or so and often you let it cool in the pot. Then you rinse and dry. And that is it. Apart from the mordanting and modifying. Mordants are important. Without them the dye will not attach itself to the fibers. The most common mordants are metal salts, like aluminium, iron and copper and they do affect the colour. As will changing the PH balance. So there is a lot to play with. And it can get complicated, but mostly it's easy and fun.
I used Icelandic wool called Lopi, which is hardly spun and pulls apart really easily. It also felts really easily, so I didn't exactly make things too easy for me. I used this wool because I thought it would be fun to use local plants to dye and then knit me an Icelandic sweater using many different colours. I haven't had a sweater since my last one fell apart, but they are nice to own and most people have them to use in summer. Because it's cold in summer. Lopi is what is used in the sweaters, so I had to use that. But it was quite a challenge to dye it because of the felting. But I managed to wind it into two small balls.
The colour was a very light yellow, not a touch of the brassy colour of the flowers, but a surprisingly light, greeny yellow, quite delicate and pretty. So now I have started this journey. I haven't given up soap but if I am to ever finish that sweater I have a busy time ahead of me gathering flowers.