Why does a mint make ice cream even colder?

All mints contain the chemical menthol, which binds to the TRP-M8 receptors in your skin which sense cold, the temperature doesn't change it's the menthol that causes false cold signals to be sent to your brain. This feeling is intensified because the ice cream also sends cold signals to your brain and this increases the number of cold receptors that are firing at once. This is similar to the reaction caused by chilli which is caused by the chemical capsaicin which binds to the TRP-V1 receptors for heat.