Mash the bananas with a fork until mostly smooth. Mix the melted cocoa butter, bananas, eggs, milk, sugar, and vanilla.
Sift together the flour, baking soda, and baking powder, then stir in the flax and salt.
Stir together the dry and wet ingredients until the dry ingredients have just been moistened. Stir in the chocolate and pecans, then pour into a prepared 5"x9" loaf pan.
Bake for 75 minutes at 325ºF until a toothpick inserted in the middle of the loaf comes out clean.