Set the oven to 350 degrees. Using an electric mixer, cream butter and sugar until fluffy—about three minutes. Add eggs and vanilla; then, by hand, thoroughly combine Add flour, salt, and cocoa powder; mix by hand until thoroughly blended. If you use a mixer, it will have more of a brownie or cake texture than gooey, so hand mix to make it gooey. Pour mixture into 8-inch pie plate after butter or cooking spray greases it. Bake until center is set 30 to 35 minutes.