Preheat oven to 350°Line a loaf pan with parchment paper.

Chop the baking chocolate with a sharp knife and set aside.

Melt butter and chocolate in a saucepan over low heat, stirring continuously until melted completely.

In a bowl, mix all of your dry ingredients, and slowly add vanilla extract, eggs, apple cider vinegar.

Add the melted chocolate to the cake mixture. Mix until well combined.

Quickly pour the batter into loaf pan and tap the bottom of the pan to get rid of any air bubbles.

Bake for 20 to 30 minutes until a knife inserted into the center of the cake comes out clean.

Allow the cake to cool before removing it from the pan.

Slice and serve.