Heat the olive oil in a large pot over medium heat. Add tomato paste, cumin, chilli powder and smoked paprika for a minute until fragrant. Add diced onion and cook until softened about 3 minutes.
Add the minced garlic and cook for 1-2 minutes until fragrant.
Stir in the diced bell pepper. If using fresh diced pumpkin instead of puree add it now. Cook for 5-7 minutes until the vegetables are tender.
Add the black beans and kidney beans to the pot. Stir in the crushed tomatoes, diced tomatoes, pumpkin puree and vegetable broth.
Add cayenne pepper, sugar, salt, and black pepper. Adjust the seasonings to taste.
Bring the chilli to a simmer, then reduce the heat to low. Cover the pot and let it simmer for at least 30 minutes to allow the flavours to meld together. Stir occasionally.
If the chilli becomes too thick, add more vegetable broth to reach your desired consistency.
Once the chilli is ready, serve it hot with your favourite toppings, such as diced avocado, chopped green onions, cilantro, vegan cheese, or dairy-free sour cream.
Enjoy your delicious and hearty vegan chilli! It's perfect for serving alone or with fresh corn tortillas and chips.