Found gel putty makes convincing stop mo water.
sigh*... Novelty gel putty entirely non-sticky, smooth textured, non-oily, odorless, and (hopefully) non-toxic, made in China.
Comes away cleanly from anything it touches, like puppets or props without leaving a trace, mark, or residue of any kind, yet stiff enough to hold it's shape, such as sculptable pouring water.
Can be worked to develop bubbles for boiling effects, or clouded for increasing level of opacity.
I looked high and low online for a link to the same material I bought in a $1 bin of party supplies but I couldn't turn it up. The closest product I could find was a clear slime novelty toy but I don't know how it compares to the way this material firmly holds form.
The test GIF** shows me that, with properly secured props and more careful animating, this substance will be an ideal solution for Rana's tea, soup, and other liquid props.
*Wrote this post then lost this post. Found Blogger "help" not found helpful. Re-wrote without same finesse.
**Made from frames stacked and animated in PS CS3 and saved to GIF format--really missing that sweet easy stop motion feature on the earlier Coolpix model for no fuss tests.