Some commentators recently have expressed confusion about the definition of critical thinking. See this previous post, for instance.
However, if you want a quick explanation from an expert on how the brain works, please have a look at this Teaching Tip from Starlink on YouTube. Here is more information on Starlink professional development.
The presenter is Lori Cook, director of pediatric brain injury programs at the Center for Brain Health, at UT-Dallas. She mentions Bloom's taxonomy in the discussion—an approach to learning used by many educators—and focuses on the collegiate level.
You may discover that you are already employing a strategy of instilling critical thinking skills in students, but didn't have a name for it. Dr. Cook's presentation is too brief for detailed analysis, but it is a good start. It's also easy to see how teachers in almost any academic discipline can find some insights with the approach.