Heat the olive oil in a large pot over medium heat. Add the chopped onion and sauté until it becomes translucent and fragrant, about 5 minutes, stirring occasionally.
Add the minced garlic and chopped chipotle peppers to the pot. Cook for another minute until the mixture smells fragrant and the peppers are slightly softened.
Increase the heat to medium-high and add the ground meat, breaking it apart with a spoon. Cook until browned and no longer pink, about 8 minutes, letting it develop a slight crust for extra flavor.
Sprinkle the cumin and cocoa powder over the meat mixture. Stir well to coat everything evenly, allowing the spices to toast for about 30 seconds, releasing their aroma.
Pour in the diced tomatoes along with their juice, stirring to combine. Bring the mixture to a gentle simmer, then reduce the heat to low.
Add the drained and rinsed black beans to the stew. Stir to distribute evenly, then cover the pot.
Let the chili simmer gently for about 30 minutes, stirring occasionally. The flavors will meld, and the chili will thicken to a rich, velvety consistency.
Taste the chili and season with salt and pepper as needed, adjusting the flavors to your preference.
Serve the smoky chipotle cocoa chili hot, garnished with your favorite toppings like shredded cheese, chopped cilantro, or sour cream if desired.