Step 1

Preheat oven to 350°F and prepare a 9x9 pan with non-stick spray or parchment paper.

Step 2

Roughly chop the chocolate and place into a bowl.

Step 3

Slice the butter into smaller pieces and add to the chocolate. Microwave for 1 minute. Stir well and then microwave for another 30 seconds. Stir again and stir until all pieces are melted and the butter is incorporated.

Step 4

Add sugar to the chocolate and butter. Stir well.

Step 5

Add in vanilla, eggs, and pinch of salt. Stir until well incorporated.

Step 6

Add sourdough starter and stir by hand until smooth.

Step 7

Pour brownie batter into prepared pan and bake for 25-28 minutes or until an inserted toothpick is removed with a few crumbs but no wet batter. Do not overbake. (Every oven is different so start checking at 22 minutes just in case!)