Preheat the oven to 375ºF. Spray your loaf pan lightly with oil, and line with parchment paper for easy removal later.
In your mixing bowl, whisk together the stevia (or sugar) and Greek yogurt. Once it goes from thick and clumpy to liquidy, whisk in the milk, egg, and vanilla.
Once you have a nice liquid base, add in the self-rising flour and salt. Fold it together until it's just combined and you have a thick batter. Do not overmix.
Spread half the batter into your loaf pan. Then, spread your cranberry sauce over top. Layer the rest of the cake batter on top of that making sure to cover the cranberries completely.
In your small bowl, combine the brown sugar and cinnamon. Sprinkle this over the top of your coffee cake batter in the loaf pan.
Bake for 40-45 minutes or until a toothpick inserted in the center comes out clean.
Cool in the pan for 10 minutes before removing to a cooling rack and cooling an additional 10 minutes before serving.