This article explores one novice mathematics teacher educator's initial use of the Mathematical Quality in Planning Protocol, an innovative tool that was developed to assist in providing feedback on the mathematical quality of novice mathematics teachers' lesson plans. The protocol was devised to help mathematics teacher educators bridge the gap between prospective teachers' mathematical content knowledge and their mathematical content knowledge for teaching. Results of our analysis on an initial use of the protocol point to its potential as a tool to help mathematics teacher educators direct their feedback from being overly focused on the pedagogical aspects of the lesson (e.g., timing, planned activities) to the mathematical content prospective teachers are attempting to teach (e.g., anticipated student solutions, problem-solving strategies).