Sociocognitive theory views learning, including second language acquisition, as the progressive alignment of individuals vis‐à‐vis their ecosocial environments. In this article we first update sociocognitive theory in light of recent evolutionary/ecological research on learning/teaching: (a) Humans are evolutionarily adapted to adapt to myriad environments, placing a premium on adaptive learning, (b) human adaptation is effected substantially through niche construction—engineering environments to make them more adaptive, and then transmitting the results culturally, placing a premium on adaptive teaching, (c) both human learning and teaching are innate/instinctive, and co‐evolved, and (d) there are many kinds of ‘teachers’ in the world. Second, we briefly review 3 approaches to second language acquisition/teaching (SLA/T) vis‐à‐vis sociocognitive theory: van Lier's ecological‐semiotic approach, Schumann's interactional instinct, and conversation analysis. Third, we apply our theoretical perspective exploratorily to videotaped data of a Japanese learner/user of English as a lingua franca who is baking pastries with a Finnish friend. Our analysis includes 5 widely studied ‘units of participation’: activity types, routines, co‐constructed tellings, repetition, and assessments. Analysis suggests that these constitute powerful environmental support structures yielding rich learning opportunities for SLA/T in moment‐to‐moment interaction. Fourth and finally, we discuss our results vis‐à‐vis our theoretical approach. We conclude by suggesting how our expanded view of teaching/learning might broaden SLA/T's ‘pedagogical imagination.’