Oh my! The instructions on the pack told me to mix two tablespoons with boiling water. No wonder I had a mess. I find my crockpot invaluable so it’s good to know that I can use these normal thickening agents.
Thanks everyone for your suggestions....
I often don't bother - I'll just not add too much liquid, but I generally use (sour) cream, yoghurt or cream cheese if I want a slightly thicker consistency. I've recently used tiny amounts of xanthan gum, added bit by bit as it certainly does tend to get gloopy or even rather solid if you're not careful with it!
Bowls and spoons also work well if you don't mind semi-soup type stews.