Based on my observations of squirrels in my garden:

Squirrels have a clear preference for:

Nuts of any kind

Bulbs, especially the more expensive ones

Figs, ideally when they are just about ripe for picking

Buttered toast, preferably a whole piece held in both paws and savored on the windowsill while enjoying the spectacle of a human attempting to exercise. It’s quite a sight to see a squirrel munching on toast while someone struggles with lunges.

On the other hand, squirrels do not seem to fancy:

Radishes

I once witnessed a squirrel cautiously pluck a radish from the ground, take a bite, immediately recoil, and fling it across the garden in utter disappointment. It seems what goes around comes around, squirrel. That radish mishap was payback for the lunges, I suppose.