Place oil into a large dutch oven over medium heat. Saute onion and jalapeno (if using) for 5 minutes then add in garlic; cook for 1 minute.
Stir in chicken broth, rotel tomatoes, beans, green chilies, lime juice and dry seasonings. Cook for 5-10 minutes; taste and add additional spiciness (jalapeno, cumin, cayenne) according to your preference.
Allow the soup to simmer for another 20 minutes. Taste the broth again and adjust the spice if needed. Note: If the soup is too spicy, add more chicken stock.
Portion the soup into bowls and serve along with suggested accouterments. Guests can then garnish according to their individual preference.