Heat the olive oil in a large saucepan over medium-high heat. Add the onion, bell peppers, carrots and 1/2 teaspoon salt; cook, stirring frequently, until the carrots begin to soften, about 8 minutes.
Add the garlic and cook 2 more minutes.
Add the chili powder, cumin, coriander, oregano, chipotle, tomato paste and tortillas and cook, stirring, until the tomato paste is brick red, about 4 minutes (add a splash of water if the mixture begins to stick).
Add the coffee and simmer until almost completely reduced, about 30 seconds.
Stir in the tomatoes, cocoa powder, beans and 2 1/2 cups water and bring to a simmer over low heat. Cook, stirring occasionally, until the chili thickens slightly, about 1 hour, 30 minutes.
Meanwhile, trim the large stems off the cauliflower and coarsely grate the florets on a box grater. About 10 minutes before the chili is done cooking, stir in the grated cauliflower. Cook 10 minutes, then remove from the heat.
Stir in the chopped cilantro and season with salt. Add some water if the chili is too thick.
Ladle into bowls and add toppings (i.e., cheese if desired).