Cook onion, bell pepper, jalapeno, celery, carrot, garlic, salt and pepper in a 5-6 qt. pot in olive oil, over moderate heat, stirring occasionally, until softened, about 6-8 minutes.
Meanwhile, mix together brown sugar, spices, oregano, thyme and mustard and then add to vegetables and cook, stirring until very fragrant, about 4 minutes. Add lentils, bay leaf and stock and simmer, uncovered, stirring occasionally, until lentils are very soft, about 50-60 minutes. Discard bay leaf before serving.
I changed from lentils to a bean/grain mixture because that is what I had on hand. I cooked with the lid on and increased the cooking time, so that the beans would get done, and I used only six cups of water. Both my husband and I liked the taste very mush and I will make this recipe again.