Metacognitive awareness enables people to make conscious decisions about their own cognitions, and adapt to meet task performance goals. Despite the role of metacognition in task performance, technologies that effectively augment metacognition are scarce. We explore a novel approach to augment metacognition based on making the eye's pupil dilations, which associate with a variety of cognitions, audible via sonification in real-time. In this exploratory study, we investigated whether pupil dilation sonification can elicit metacognitive awareness. Our findings suggest that correlations between a variety of cognitions, e.g., attentional focus and depth of thinking, and sounds generated by the sonification can emerge spontaneously and by instruction. This justifies further research into the use of pupil dilation sonification as a means to augment metacognitive abilities.