Fudgy Sourdough Brownies

 9 oz semi sweet chocolate, chopped
8 oz butter
8 oz sugar
4 oz brown sugar
1/2 tsp salt
1 Tbsp vanilla
3 large eggs
8 oz sourdough discard
2 1/2 oz all purpose flour

Preheat oven to 350.  Grease a 13x9 pan.  Combine 9 oz semi sweet chocolate and 8 oz butter in large microwave safe bowl.  Microwave in 15-30 seconds increments, stirring after each one, until fully melted.  Add 8 oz sugar, 4 oz brown sugar, 1/2 tsp salt and 1 Tbsp vanilla, stir to combine.  Add 3 eggs, stir until combined then stir vigorously for 30 seconds.  Fold in 8 oz sourdough discard.  Add 2 1/2 oz all purpose flour and stir just until combined.  Spread batter evenly into prepared pan.  Bake until brownies puff a bit and toothpick inserted in the center comes out with a few moist crumbs (about 30 minutes).  Cool in the pan to room temperature then refrigerate until the brownies are firm.