Okay, I know it sounds like Alias Grace but it isn't. I've read that too.
I think it's set in America, possibly late 1800s/early 1900s. The master of the house and I think his wife are found murdered. The story is from the POV of a female servant and there's another female servant who lives next door that she talks to when she is in the garden hanging laundry?
I think the plot switches between the present and then back to the lead up to the murders and there's numerous mentions of a stew on the kitchen stove that people keep eating from even though its rancid and probably making people unwell. I think someone is sick in the parlour because of it? Oh and there's a barn. Something about a barn.
Is this a book? A film? Help!!