Rinse the lentils under cold water. Place in a pot with the vegetable broth. Bring to a boil, then reduce to a simmer. Cover and cook for 20 minutes until tender. Remove from heat, keep covered for 10 more minutes.
While lentils cook, make the enchilada sauce: heat olive oil in a skillet over medium heat. Add spices and cook 2 minutes. Stir in flour and cook 1 more minute. Add tomato sauce, bring to a boil, then simmer until thickened, about 5 minutes. Set aside.
In a separate skillet, heat 1 tablespoon oil over medium heat. Add onion and garlic, sauté 3–4 minutes. Add bell peppers, tomato, grated carrot, and chili peppers. Sauté 5–7 minutes. Remove from heat.
Add oats, sunflower seeds, ground chia seeds, spices, salt, and pepper to a food processor. Blend 20–30 seconds.
Add the sautéed vegetables and tomato paste. Blend again until combined.
Add cooked lentils. Blend until the mixture is thick and holds together. If too loose, add more ground oats and pulse again.
Preheat oven to 390°F (200°C). Grease a baking dish with oil.
Spread about 2 heaped tablespoons (100g) of filling onto each tortilla. Roll up and place seam-side down in the baking dish. Repeat with all tortillas.
Pour the enchilada sauce evenly over the rolled tortillas. Bake uncovered for 15 minutes.
Remove from oven. Add vegan cheese sauce or shredded vegan cheese on top. Return to oven and bake another 10–15 minutes until bubbly and golden.
Garnish with fresh cilantro. Serve hot with vegan sour cream if desired.