3.

Whisk sugar and vanilla into bowl. Whisk in eggs one at a time. Add chile powder, cinnamon, cayenne, salt, and espresso powder and whisk to combine. Add flour and stir just until combined. Stir in chocolate chips, then transfer batter to prepared pan. Smooth top. Bake just until a cake tester inserted into the middle of the brownies comes out clean, about 30 minutes. Let cool completely then cut into squares.