Preheat oven to 350°F.
Line a 13x9 inch baking pan with parchment parchment paper, making sure the ends extend over the side. Spread softened butter over parchment paper.
In medium bowl, mix cranberries, sugar, gelatin and orange zest. Pour into bottom of pan and press into a single layer.
In large bowl beat cake mix, dry pudding mix, eggs, water, orange juice and oil with mixer, just until fully mixed. Pour batter over cranberries and gently spread to an even layer.
Bake 42 to 46 minutes or until toothpick inserted in center comes out clean.
Cool completely. Carefully invert cake on to platter, removing the pan and parchment paper.
Serve at room temperature or cold with whipped cream and fresh mint and fresh cranberries for garnish, if desired.