In a medium pot, heat the 1 tablespoon of olive oil over low heat. Add the chopped onions and leeks, sautéing for about 5 minutes until they start to soften. Stir in the minced garlic, cumin, and coriander, cooking for a few more minutes until fragrant.
Next, add the smoked paprika, cinnamon, chili powder, cocoa, and dried oregano. Pour in the can of diced tomatoes, 3 cups of water, and chopped carrots. Bring the mixture to a simmer, then cover and cook for 20 minutes, or until the vegetables are tender and the chili has thickened. Give it an occasional stir and add a splash more water if it looks too dry.