Assessment plays a significant role in determining the quality of education. This is particularly so when students are properly assessed using various appropriate methods of assessment. This study investigates teachers' assessment methods and the challenges they encounter in assessing learning in an Ethiopian university. A convergent parallel mixed-method research design was used. A total of 166 from 210 sample teachers completed and returned the questionnaire. Moreover, six heads of departments and six teachers were selected for the interview. The results indicate that teachers largely depend on written assessment methods against innovative/alternative methods that would have been used to uncover students' creative and proficiency in their study areas. However, teachers encounter challenges as they attempt unfamiliar (but innovative) assessment methods. The study reveals that making the students creative and proficient in their study areas is simply untenable if teachers continue to utilise current assessment practices. This study acknowledges the contribution of effective assessment to making the students proficient in their study area. Implications of the current assessment practices are discussed and consequently, recommendations for the enactment of innovative/alternative methods are made.