Complex sentence: Constance bakes chocolate cupcakes laced with ipecac syrup and brings them to Vivien, insisting that they be given to Violet, masquerading them as an apology gift for Adelaide's continued intrusion in the Harmon's home.
Split into simpler sentences: Constance bakes chocolate cupcakes laced with ipecac syrup and brings them to Vivien, insisting that they be given to Violet. She tells Vivien that they are an apology gift for Adelaide's continued intrusion in the Harmon's home.