I know some people are going to say "it's slice of life, it doesn't have to be about anything!" and they are right to an extent, but this really does just feel like it's spinning its wheels and not even trying to do anything with the characters. It's entirely just about him experimenting with food now instead of how his cooking was able to connect him to people. Like... remember when Ai Fa was actually an important character and not just someone who occasionally popped up in the background when he was testing recipes?
It kinda feels like all those other "________ otaku" types of stories where investing in the minutiae of the hobby are what really gets the author going instead of the characters and plot. Like Sono Bisque Doll/My Dress-up Darling did that after a while, turning from "fun character piece about people connecting through cosplay" to "LOOK AT ALL THE STUFF I LEARNED ABOUT COSPLAY! HERE ARE MY AUTHOR'S NOTES IN UNEDITED FORM SO YOU CAN LEARN ABOUT THE GLORY OF COSPLAY AND COSTUME CONSTRUCTION IN EXCRUCIATING DETAIL! oh and also sometimes the characters are there and not just cosplay delivery vehicles."
I also noticed that this is a series with separate author and artist and I wonder if the artist is becoming disinterested in the plot too and that's what's driving the degradation of the art quality.