The cake which Fran brings out, apparently helping Rory to decide that stealing from little old ladies is a good thing.
Mocha is a combination of chocolate and coffee, and this cake is a chocolate one filled with mocha buttercream, and decorated with nuts to give it the necessary “crunch”. No wonder that a caffeine-laden cake filled with coffee is what finally convinces Rory to abandon any thoughts of ethical behaviour when it comes to free cakes.