very low heat, stirring occasionally. when the chocolate is just about blended, remove from the heat and continue to stir until the mixture is smooth.
3. transfer the mixture to a bowl and stir in the sugar. then beat in the eggs, one at a time. add black beans and combine.
4. gently stir in the flour, salt, and vanilla. add in 1/2 cup of the chocolate chips. pour and scrape into the prepared pan.
5. top with remaining chocolate chips and bake until just barely set in the middle, 20 to 25 minutes. it's better to under bake brownies than to over bake them. cool on a rack before cutting. store, covered, 