Well, oat milk.

Using 10:1 water/porridge oats by weight, which works out 3:1 by volume with
he oats I used (Flanagans), 20 seconds in a liquidiser, through a tea strainer
twice - produces decent oat milk, very similar to shop bought. Slightly
sweeter, but not as sweet as cow's milk, and doesn't separate in tea or
coffee.

There's still some sediment, and it doesn't auto-homogenise, so needs shaking
before use. Straining through a tea towel or similar might help, and some shop
bought types have certain additives like oil and flavourings (I think) that I
might try - but so far, so good.

You're welcome :-)

--
Cheers, Rob