Should I fill as a liquid or allow to set and whip it first?

Personally, I would whip so it would be a light, fluffy filling.

Agree...whipping it will make a wonderful filling.

I would allow it to set, but not completely, then pipe it into the cupcake. It would be like a cupcake with a chocolate truffle in the middle. YUM! Just thinking about it makes my mouth water. LOL!

For speed and ease, I fill mine with room temp ganache, and use a squeeze bottle while the ganache is still fluid. SUPER FAST and CLEAN!!

Thanks I think I'll try both ways!

I whipped mine this past weekend (white cupcake, white chocolate ganache inside, topped with white IndyDebi buttercream for a "white" anniversary party) and people loved it!