The Thin Woman, by Dorothy Cannell

This book is simply a hoot! Soon after a family reunion to which heroine Ellie has brought a hired escort posing as her fiancé, Elly's uncle dies, leaving her his estate and a buried treasure, provided she and her "fiancé" marry and live together in the castle for six months. Bentley, a down on his luck master chef is as taciturn as he is handsome and furious at being reduced to being a paid escort, agrees to Elly's proposition to marry for the requisite six months for a portion of the prize. Ellie and Bentley search for the buried treasure while falling in love...and losing weight. The perfect romance!

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