© 2019 JLLS and the Authors - Published by JLLS.Turkish Council of Higher Education (CoHE) has updated the curriculums of teaching programmes recently by increasing the percentage of the elective courses. This change became the focus of this study. The study aims to find out the four most preferred General Knowledge (GK) elective courses among English language teachers and the criteria that determine their preferences and to design a syllabus for the most preferred course. It incorporated two phases and in the first phase, mixed method sequential exploratory research design was carried out. Having reviewed the curriculums of ELT departments of all 45 state universities, the researchers made a document analysis on the GK electives and developed a questionnaire which was conducted to 1093 participants online. The data were analyzed by Microsoft Excel and SPSS 21.0. Mixed method sequential transformative research design was used in the second phase. Having done a document analysis, a questionnaire was developed, and administered to 114 English language teacher educators online. The data were analyzed by Microsoft Excel and SPSS 21.0. The findings of the first phase indicated that the four most preferred GK elective courses were ‘Diction’, ‘Presentation Skills’, ‘Human Relations and Communication’ and ‘Language and Culture’, and ‘personal needs and interests’ was the most important criterion. From the results of the second phase of the study, 18 topics were specified to suggest a topic-based syllabus for ‘Diction’. Based on the findings of the study, some implications for ELTPs and for further research were presented at the end of the study.