Heat oil in a soup pot over medium heat. Add onion and saute for 1-2 minutes. Add garlic and jalapeno and sweat until soft and translucent. Add spices and cook for 1-2 minutes until fragrant and aromatic. Add tomatoes, chicken, Worcestershire, and stock. Bring to a simmer and cook for 20 minutes. Cut the lime in half, squeeze juice into the pot, and then add the juiced halves as well. Add rice and cook 5 minutes longer to warm rice through. Season to taste with salt. Ladle into bowls and garnish with avocado slices and cilantro.