This study aimed to make a cake by incorporating chia seed flour (CSF) at 0, 3, 5, and 7% with egg replacement at 0, 25, 50, and 100%, respectively. The addition of CSF increased the total proteins, fats, and mineral contents. However, cake volume, uniformity, and symmetry were lowered significantly (
p
>
0.05
) at an elevated level (5% and 7%) of CSF. Similarly, the cake depicted relatively higher textural hardness, springiness, cohesiveness, and chewiness upon addition of CSF. The higher substitution of CSF resulted in darker crust and crumb with lower sensory acceptability by the panelists, though the 3% CSF addition did not compromise the cake acceptance. Nonetheless, there were a significant rise in total phenolics and better antioxidant activity with CSF, measured as free radical scavenging activity. Most importantly, a massive rise in unsaturated fatty acids (ω-3, ω-6) and the simultaneous decline in total cholesterol were detected with increasing substitution of CSF.