(Within reason, mind. She’s been told this can only happen at home.)
I don’t want to stifle The Child’s capacity for asking herself questions (eg. What happens if I do this?) and actually trying to answer those questions with ‘experiments’. Having had a fussy eating childhood myself, I’d also like her to think of food as fun, and not something to get told off about.
Parents know their children well enough to be able to tell if their toddler is being inquisitive, or has decided to see how far they can push the ‘naughty’ boundaries. It’s a look in their eyes — there’s a definite twinkle there when they know they’re being naughty.
In the above instance, I stopped her and cleaned up after she started rubbing the porridge into the table, because she knows exactly what happens when she does that.