Majority of the institution still use inefficient open fired indoor wood based biomass stoves to fulfill their energy consumption. Due to this much of the thermal energy comes from the wood lost to the surrounding. Besides Women are the primary victims of the kitchen air pollution due to excessive wood burning. Improved fuel saving stoves like Institutional mirt stove was developed in the mid-2010s by Energising Development (EnDev) Ethiopia program for commercial bakeries. Even if the stove is among the improved stoves, it has high amount of waste heat by the flue gas and lower durability of the stove especially the chimney support (seat), this may be due to the chimney seat is exposed to very high temperature of flue gasses coming out from its four independent mirt combustion chambers. In this study an attempt has been made to improve the efficiency of the existing institutional mirt stove with waste heat recovery system, which uses waste heat from the exhaust flue gases of Institutional mirt Stove as the source of energy for injera baking oven system. The performance of the designed and manufactured prototype cooking stove is evaluated using CCT version 2.0 software. The result shows that the improved stove saved up to 16% fuel wood and14% cooking time using waste heat recovery system compared to the Institutional mirt stove. During the test a temperature of about 216.3 ℃ on the baking pan surface is achieved and injera is baked on this surface. The benefit/cost ratio of improved stove with waste heat recovery system is 30.12. This indicates that the project is economically acceptable.