Black Sesame Fudge Brownies

Melt the dark chocolate and unsalted butter gently in a heatproof bowl over simmering water until the base is completely smooth. Stir in the sugar, then add the eggs one at a time so each is fully incorporated and the batter develops an even gloss. Black sesame paste goes in after the eggs and must be spread through the entire chocolate mixture without streaks or clumps. Sift the flour, cocoa powder, and salt together, then fold only until the dry marks disappear. Brief mixing at this stage preserves the close, fudgy crumb. Spread the batter in a parchment-lined square pan and bake at 175C. Remove it after 26 to 28 minutes, when the edges are set and the center still appears slightly moist. Residual heat continues to cook the center as the pan cools. Wait until the brownie is completely cool before slicing so the dense interior can settle and the cut edges stay clean. Chilling it before cutting produces even sharper corners and a firmer bite.