Mousse TV ad with talking moose and mouse. Anyone?

[Hugo Drax]

Can anyone identify a British TV ad, probably 90s, for a mousse dessert (choc?) that featured auditions of animals trying to say 'mousse'? There was a mouse that spoke high-pitched, and a moose with a very deep voice. Definitely didn't imagine it, as my sister and I used to replicate the parts for years after.

Can't find it on YT, so wondered if anyone knew. Cheers.