There's some chilli in the recipe. When I'm not sure, I add it gently a bit at a time in the form of dried chilli flakes rather than fresh chilli peppers. I think you need a little to give it a lift, though chilli isn't really the point of the thing. You're aiming for warming and mild. I'm very wary of bought chillis. I never know how much to use. I've just made a huge batch of chilli con carne with four pounds of meat. I used two small red chillis from Sainsburys that were supposed to be "medium", half a dried ancho chilli and a dash of sweet chilli relish, and it doesn't need any more and I love chilli!