Bakers are raving about a photographer's 'Basque burnt cheesecake' made from flour, eggs, sugar, cream and a $3.30 'secret' ingredient: Philadelphia cheese. Arwen Genge, 43, from Hobart, used a simple recipe developed by Melbourne restaurant critic Dani Valent, who fell in love with the decadent dessert on a trip to San Sebastian in the Basque region of northern Spain in …