In a large pot, heat olive oil over medium heat. Add peppers, onions and celery and cook until softened, 3 to 4 minutes. Add garlic, chili powder, paprika, cumin, and oregano and sauté until fragrant, 1 to 2 minutes more. Season with salt and pepper.
Add beer and cook until it has reduced by half, about 6 to 8 minutes, stirring occasionally. Add sweet potato, black and pinto beans, tomatoes and vegetable broth. Stir and bring to a boil, then reduce to a simmer and cook until slightly reduced and sweet potatoes are cooked through, 30 to 35 minutes.