While learning and teaching English as an additional language are lifelong learning processes for both learners and teachers, these two sectors are largely dominated by West-centric linguistic and cultural imperialism, epistemic hegemony, racism, and neoliberalism, which are tied to colonialism and imperialism. In light of this issue, I argue that it is necessary to decolonize and de-imperialize the teaching English to speakers of other languages (TESOL) teacher education curricula to prepare future English as an additional language (EAL) teachers to identify, challenge, and resist the hegemonic elements embedded in EAL education worldwide. I claim that plurilingual pedagogical approaches can be identified as critical pedagogies since they can empower adult EAL learners by resisting linguistic and epistemic imperialism through activation and endorsement of their plurilingual repertoire, diverse knowledge systems, and identities. Drawing on the literature of plurilingualism, decolonization of knowledge production, and curriculum design, this article discusses how plurilingual approaches can be combined with critical and transformative pedagogies in a TESOL curriculum for the purpose of training future EAL teachers to empower their adult EAL learners globally. These curriculum suggestions are relevant to TESOL curricula to illustrate how plurilingualism and decolonizing theory can be put into practice.