Just a basic, spicy vegetarian chili.
Heat oil in large pot over medium-high heat. Chop the onion in small squares. Add the onions to the oil and saute, stirring occasionally, until they soften and turn golden brown - about 20-30 minutes.
Coarsely chop the bell peppers, and mince the garlic or prepare it for pressing. Dice the jalapenos, if using them.
Turn the heat down to medium, add the bell peppers, jalapenos (if using) and minced/pressed garlic to the pot, and cook for another 10 minutes.
Open the cans of beans, tomatoes, and corn. Drain the cans of beans and can of corn.
Mix in chili powder, oregano, cumin, and cayenne and stir constantly for about 2 minutes.
Mix in beans, diced tomatoes (with liquid), and corn. Turn heat up to medium high or high and bring chili to boil, stirring occasionally. Reduce heat to medium and simmer for at least 30 minutes, stirring occasionally. This can simmer basically indefinitely, so continue to simmer until shortly before you're ready to serve.
Serve with sour cream and/or grated cheese available for people to mix in as desired.