Name a fruit or vegetable that is red on the inside.
Beefsteak fungus
Beefsteak fungus bleeds a dull red juice when cut, like raw meat.
African peach
The African peach (Nauclea latifolia) has sweet, edible pink to dark red flesh, so it fits a fruit red on the inside.
Source:en.wikipedia.org
Arctic raspberry
Rubus arcticus, the Arctic raspberry, bears deep red or dark purple edible fruits, fitting a fruit red inside.
Sources:en.wikipedia.orgrhs.org.uk