"The Joy of Cooking"

"The Joy of Cooking" by Elaine Magarrell is a bit of a weird poem actually!  However, I think I can make sense of it!  "I have prepared my sister's tongue."  This was one of the lines the speaker said; however, people cannot take this literal in poetry (at least I don't think).  Possibly, the speaker is implying that her sister says dumb or mean things.  Possibly, she is a gossiper or something of the sort.  I think the speaker has just had enough of the stuff her sister says, and she is expressing how she feels.  With brother, I think the speaker is trying to express that her brother is mean.  She describes dipping the heart in sour sauce, so maybe the brother has a sour personality.