In the skillet, sprinkle in the ground cumin, cayenne, and then add the cinnamon stick, saute about 1 minute. Add the rice and cook, stirring often but gently until some rice grains start to brown. Add the cooked lentils, 3 cups of water and 1 teaspoon of sea salt and bring to a boil. Turn the heat down to a simmer, cover and cook 30 minutes. The water should be completely evaporated and rice should be tender. If there is still too much water in the skillet, put the lid back on and cook for another 5 minutes.