Background: The development of higher-order thinking skills (HOTS) in problem-based learning (PBL) is not confined to teaching and learning but extends to authentic assessment methods, similar to real-life situations. The assessments aligned to PBL attempt to eliminate the students’ tendency towards memorisation. Rather, it instils and encourages their ability to analyse, interpret, synthesise, and evaluate knowledge and its sources.Aim: The study had two primary aims: (1) to describe undergraduate nursing students’ experiences of an online problem-based assessment (PBA), and (2) to explore how online PBA assessment contributed to the development of undergraduate student nurses’ HOTS.Setting: An urban-based South African higher education institution (HEI) in KwaZulu-Natal, Durban, South Africa.Methods: A descriptive, exploratory qualitative approach was used. The target population was 4th-year psychiatric nursing students (N = 39) studying for the degree of Bachelor of Nursing at the preselected university, utilising two focus groups (n = 5, n = 7). Data were analysed through content analysis using the clinical reasoning model as a framework.Results: Three categories (trigger problem, re-visioning the cues, treatment direction) and seven sub-categories (trigger problem posing, early cue identification, cue interpretation and clustering, focussed cue investigation, information processing and interpretation, reprioritise hypotheses, and diverse intervention[s]) emerged.Conclusion: Psychiatry, Nursing and Midwifery practices require a practitioner skilled in HOTS to provide quality, efficient and cost-effective patient care.Contribution: The findings in this study can benefit nursing education, particularly learning interruptions in HEIs.