Rationale Undergraduate nursing students' learning opportunities to practice caring behaviours to assure compassionate and competent nursing practice with standardised patients are few. Earlier studies primarily focused on practicing communication skills in relation to mental health or developing psychomotor skills while caring for a patient with a specific diagnosis. Aim The study aim was to describe undergraduate nursing students' experiences of practicing caring behaviours with a standardised patient. Method A sample of forty-eight undergraduate nursing students in semester four at a school of nursing in southern Sweden, enrolled in a full-time, 5-week, on-campus elective caring behaviour course, were at the first and last week individually video-recorded during two caring behaviour simulations encountering a standardised patient. After observing each of their video-recordings, students completed written reflections focusing on their own compassionate and competent verbal and nonverbal caring behaviour. In total, 96 individual written reflections were analysed using qualitative content analysis to describe the experience. Results One main theme emerged: The challenge of being mindfully present in patient encounters. Four themes further described the experience: A challenging but realistic learning experience, learning the impact of nonverbal behaviour, recognising the complexity of verbal behaviour, and learning to be with the patient instead of only doing for the patient. Conclusion When caring is intertwined with visible and realistic nursing practice in simulations using standardised patients it facilitates undergraduate nursing students learning compassionate and competent caring behaviour. The learning experience opened the students' eyes to the impact of practicing caring, recognising that being with is not the same as doing for the patient, and thus, how challenging it is to be mindfully present in patient encounters. Designing caring behaviour simulations with standardised patients is a feasible and efficacious educational learning didactic to facilitate students' learning caring behaviour and enhancing patients' experiences.