Heat oil in a large pot over medium heat. Once the oil is hot, add the chopped onion and carrot, and cook, stirring often, until the onion has softened, about 5 minutes. Add the cumin, thyme, and garlic powder. Cook until fragrant, about 30 seconds.
Add the canned tomatoes, lentils, broth, water, and red pepper flakes to the pot, and stir to combine.
Covert the pot, and increase the heat, and bring the mixture to a boil, then reduce heat to low, and simmer, uncovered, for 30 minutes, or until the lentils are tender but still hold their shape.
Carefully pour 2 cups of soup to the bowl of a blender, and puree until smooth. Pour the blended soup back into the pot, add salt and pepper ,and stir to combine. Taste for seasoning, adding more salt and pepper as desired. Garnish with fresh thyme, if desired.