If one left a A/B tek in the cupboard, and it seems to have evaporated, is it possible to continue extract from this without adding water? How does one safely go about using this material? Thank you very much nexians!

Need more info than that.

Which step?

After I basified the MHRB mud from the A/B. It had less than a pull off of it. Thank you Psilosopher

Just add the water very slowly.
If it dried totally into a cake of lye and salt and so on you need to be even more slower.
Just add water dripwise waiting between each addition for it to cool down.
Then just continue with pulling after you added the amount of water that was in it before it dried out.