In large bowl, cream together the softened butter and sour cream. Add sugar and blend well. Add eggs, one at a time, mixing well after each one. Add half & half, blending well; then stir in cocoa powder and mix well. Add the flour and blend well; then fold in the mini semi-sweet chocolate chips. Put batter into the prepared 9×5-inch loaf pan and bake at 325 degrees for 70-80 minutes, or until toothpick inserted in center comes out clean or almost clean (because it’s so dense and fudgy, the toothpick may not come out entirely clean.