Preheat the oven to 350°F. Grease a 8½"x4½" loaf pan or a 8" cake pan.
Sift coconut flour and baking powder; set aside.
Melt the butter with cocoa powder until melted and smooth. Set aside to cool slightly.
Stir in the sugar, salt and vanilla extract. Add eggs one at a time and whisk until smooth and combined.
Add the coconut flour mixture and mix until well incorporated. Finally stir in the dried cranberries. Pour the batter into the prepared pan and set aside for 10 minutes.
Bake for 35~45 minutes in the loaf pan; 30~35 minutes in the 8" square pan until a toothpick inserted in the center comes out clean.
Let the cake cool in the pan for 30 minutes before removing from the pan. Let the cake cool completely before slicing.