Cooled electronic systems and cooling methods are provided, wherein a field-replaceable bank of electronic components is cooled by an apparatus which includes an enclosure at least partially surrounding and forming a compartment about the electronic components, a fluid disposed within the compartment, and a heat sink associated with the electronic system. The field-replaceable bank extends, in part, through the enclosure to facilitate operative docking of the electronic components into, for instance, one or more respective receiving sockets of the electronic system. The electronic components of the field-replaceable bank are, at least partially, immersed within the fluid to facilitate immersion-cooling of the components, and the heat sink is configured and disposed to physically couple to the enclosure and facilitates rejection of heat from the fluid disposed within the compartment when the field-replaceable bank of electronic components is operatively inserted into the electronic system.