Do they serve breakfast everyday?

Yes

They have breakfast 7days a week its better during the week

I think they only serve breakfast on the weekends I have never seen it done on the weekdays except for special occasions. it's possible other Golden Corral's do but I'm almost 100% certain that the one in Mishawaka only serves it on the weekends and not the weekdays their hours of operation say 10 a.m. except for on the weekends or when it earlier for breakfast.