I'm also from the southern hemisphere. The kitty that I've posted does this mostly in December and January; these days she has been burying herself in the blankets instead, except through the veranico*.

It's also possible that your kitty decided that the sink is "her" place, a bit out of habit. Or that she's attracted by the smell of food, as you've said.

*dunno the English name, it's the few winter days that are almost summer-like, usually around July. Oddity of my city.