The complexity of language learning may be expanded to learning the languages belonging to the same language family, for example, Slavic languages. This paper reports on the reflection-on action research aimed at the increase of learners' multicultural competence and enhancement of critical thinking at the interdisciplinary, blended course of Slavic languages and cultures. The course organized in modules is implemented in Moodle. Course content is designed by the teacher; however, Slavic languages are presented by native speakers of these languages. Learners have an opportunity to get familiar with Slavic languages, history, and culture from the presenters' perspective, what generally results in the increase of learners' multicultural competence and enhancement of critical thinking. Learning experience is intensified through reflective learner logs, which serve as a knowledge-sharing medium and cognitive learning. [For the complete proceedings, see ED600837.]