In a large bowl add the cream cheese, egg, sugar and flour. Blend until smooth.
Pour cream cheese mixture all over the bread. Using a knife push down through the cream cheese mixture, into the chocolate batter, and swirl your knife around all over the bottom half of your loaf pan, without scraping the bottom if possible.
Add your remaining batter on top of the cream cheese mixture. Smooth the top with a knife and push batter into the corners as necessary. I also sometimes stick the knife down into the pan at this point too. I just love the cream cheese swirl everywhere. It is up to you. Just make sure the top of your loaf is as flat as possible as it enters the oven.
Bake for 60 to 70 minutes or until toothpick inserted in centre comes out clean. Watch where you stick the toothpick in. The toothpick test isn't as accurate with all of that cream cheese swirl and chocolate pieces! Just make sure the bread has baked until the top is like a dome.
Allow pan to cool on a rack for at least 10 minutes.
Remove pan and place bread directly onto your rack until cool. Once cool make your glaze, if you are using it. This step is optional. My husband thinks the glaze is unnecessary and I do not! You will have to decide for yourself!