Characterizing a critically-thinker second language learner as well as the way such characteristics can be developed and implemented in instructed second language have received momentum in applied linguistics. As a novel practice, this mixed-methods study was designed to feature a critically-thinker reader in developing both her critical thinking and reading abilities in the light of two novel instructional mechanisms (i.e., Asynchronous Web-based Collaborative (AWC) vs. Question-Answer-Relationship (QAR) instructional approaches). To this end, a sample of 89 Iranian EFL learners (Pilot group) were interviewed based on which first the features of a critically-thinker reader were extracted, analyzed and modeled via MaxQDA. Then, three groups of 154 language learners (i.e., Control, QAR & AWC) were exposed to its specific type of instruction. In addition to the extraction of "argumentation", "judgment", "dispositions", "action", "social cognition", and "creativity" each with its sub-categories as the sub-traits of critically-thinker's conceptual model, ANOVAs were run to analyze the quantitative data. It was observed that AWC group outperformed others both in critical reading and critical thinking features. So, it is theoretically and pedagogically implied that the developments of both cognitive traits (i.e. critical thinking) and the resultant language skills (i.e. reading skill) are subject to appropriate instructional approach/s.