Combine yeast, warm milk, and sugar in a large bowl (the one used for your stand mixer if you have one); let stand for 10 minutes (or until foamy.)
Add eggs, vanilla and orange zest to yeast mixture and mix well.
Sift together flour, cocoa powder, cinnamon and salt in a medium mixing bowl.
Add dry mix, ½ cup at a time, to yeast mixture. Combine after each addition using stand mixer until just incorporated. If you use up all of your flour mixture and dough is still too sticky to remove from the stand mixer bowl, continue to add more flour until dough is JUST elastic enough to work with.
Coat another medium mixing bowl with shortening. Place dough in greased bowl and toss to coat. Cover with a dish towel and let rise in a warm place (free from drafts) for at least one hour or until dough has doubled in size.
Preheat oven to 350 degrees Fahrenheit. Spray paper Panettone mold with cooking spray.
Toss dried cranberries and chocolate chips in powdered sugar. Turn dough out onto a floured surface and incorporate cranberries and chocolate chips, kneading until combined.
Form dough into a ball and place in Panettone mold. Cover with a dish towel and let rise in a warm place for another half hour.
Once dough has risen, brush with melted butter. Place in oven and bake for 45 minutes, or until loaf makes a hollow sound when tapped. Let cool slightly before serving.