We investigate the instructional coaching interactions between a kindergarten teacher and an experienced coach using the analytic lens of dialogic teaching. The data were collected in the context of a US professional development project that supports urban elementary school teachers in enacting critical sociocultural teaching practices. We illustrate how the coach assisted one teacher in developing an understanding of "Critical Stance" as a pedagogical principle in her kindergarten class that included many English Learners. Analysis of the coaching sessions shows that, to this end, the coach predominantly used "dialogue as inquiry," establishing a non-hierarchical relationship within which she and the teacher were able to co-construct a practical understanding of Critical Stance as a teaching practice. We argue that it is through the strategic use of dialogue as inquiry that the coach cultivated a dialogic space in which the teacher was invited to challenge, explore, appropriate, and eventually enact Critical Stance in her teaching. The analysis further indicates that the experience of dialogic interaction in the coaching sessions led the teacher to appropriate a "dialogic stance" and space in her classroom with her kindergartners.