Firstly, warm a large pot over medium heat and add the oil. Add the onions and cook until they become translucent and start to smell slightly sweet. Do this for around five to seven minutes.
Add the peppers and cook, stirring regularly, for 10 minutes, until softened.
Add the garlic and cook for two to three minutes, until it loses its raw smell. Add the tomatoes, beans and their stock (or the beans plus a little extra veg/chicken stock if using tinned, sweetcorn and stock.
Bring this to a simmer and let it bubble gently for 15-20 minutes until you have a rich, thick soup.
Taste and add salt and pepper to your liking. To serve, ladle the soup into bowls and let everyone add their favourite toppings.
