1 1/2 sticks butter

10 oz. semi sweet chocolate

2 tbsp. tahini

4 large eggs, room temperature

2/3 cup (58 g.) unsweetened cocoa powder plus 1 tbsp. for pan and more for dusting

1/2 teaspoon baking powder

1/2 teaspoon kosher salt

Set oven rack in center of oven and preheat oven to 350°. Butter and 9 inch round spring form pan then dust with cocoa powder.
In a large microwave safe bowl or in a heatproof metal bowl set over a pan of simmering water (water cannot touch bowl) combine butter, chocolate and tahini. Stir occasionally until melted and smooth. This may take up to 15 minutes. Remove bowl from the pan and set on counter to cool for 5 to 8 minutes.
In a large bowl whisk eggs until fully combined in lightly yellow and frothed.
Sift the cocoa, baking powder, and salt into the chocolate mixture and whisk to combine. Place the bowl of eggs on something that will prevent it from sliding. While whisking pour chocolate mixture into the eggs until a cohesive smooth mixture forms.
Pour mixture into pan and bake until the top is crackly and poofed about 30 minutes. Remove from the oven to cool for 30 minutes. Remove from springform and dust with cocoa powder.