Earlier this week I dug up a load of dandelion roots so I cleaned them and dried them so I could have a go at dandelion coffee. I dug out my copy of Richard Mabey's Food for Free and it was very vague so I looked up a few websites for more info.
In the end I roasted the roots at gas mark 6 until they were dry and crumbly (but they hadn't gone very dark), ground them up in a pestle and mortar and ended up with only 1 tablespoon of bits.
I put the bits in a jug, poured over a cup of boiling water and left it a few minutes before straining into a cup. I think I probably needed more roots because the drink was a bit weak but most noticeably it didn't resemble anything coffee-like at all (I am reminded of Arthur Dent and his cup of something which was "almost, but not quite, entirely unlike tea").
The flavour was like a cross between unsalted potato crisps and something a bit like parsnips. I'm not sure whether to try again the next time I dig up some roots but my first attempt wasn't great. At least it was better than the cornsilk tea or the hyssop tea, which were my previous attempts at drinks from the garden.