Due to the increasing presence of the Science, Technology, Engineering, and Mathematics (STEM) education paradigm in Spain, many teachers have embarked on the design of specific Teaching--Learning Sequences (TLS) to be implemented in schools. Understanding the views and perceptions about STEM that take shape in specific teachers' designs should enrich the way in which STEM education is designed based on a more focused approach. This study aims to characterise how secondary school teachers from Catalonia (Spain) design STEM TLS, to identify specific design profiles that can be related to different understandings of STEM education based on a mixed-method analytical approach. We collected 345 canvases from teachers participating in a national STEM education training programme, outlining STEM TLS. The canvases were analysed with an assessment rubric consisting of 8 instructional components (Interdisciplinarity, STEM practices, Information and Communications Technology tools, Formalisation, Openness, Alignment, Authenticity and Values). We identified patterns in teachers' designs while implementing a hierarchical cluster analysis of the results, obtaining 6 different clusters of 39, 36, 66, 49, 90, and 65 TLS, respectively. The diverse components prioritised or balanced in each cluster suggest how STEM education can be conceived of differently by participating teachers through the lens of component analysis. While authenticity appears to be a major force in the clustering process, direct relationships between components can be found (i.e., between Formalisation and Alignment), as well as inverse relationships (i.e., between Openness and Practices). These findings provide important clues to understand STEM TLS design and recognise the rubric and the cluster definition as powerful tools for teacher training and evaluation in STEM education.