Heat olive oil in a large pot over medium heat. Add diced onion plus a big pinch of salt and pepper. Cook 4–5 minutes, stirring often.

Add garlic, chili powder, cumin, and sugar. Cook 1 minute, stirring constantly.

Stir in diced tomatoes, chipotles in adobo, black beans, red lentils, and another pinch of salt and pepper.

Add tomato sauce and 2 cups vegetable broth. Cover and bring to a simmer over medium-high heat.

Reduce heat to medium-low and simmer 5–7 minutes, stirring frequently, until lentils are tender. Add up to 1 more cup broth if you want it thinner.

Stir in lime juice. Taste and adjust salt and pepper.

Serve hot with desired garnishes (Fritos, vegan sour cream, cilantro, jalapeño).