- In a pot over medium heat, heat oil. Add bananas and fry until lightly browned. Remove from pan and drain on paper towels.  
- Add potatoes and fry until lightly browned. Remove from pan and drain on paper towels. 
- Remove excess oil except for about 2 tablespoons. Add onions and garlic and cook until softened.  
- Add chicken and cook, stirring occasionally, until lightly browned and juices run clear.  
- Add fish sauce and cook for another 1 to 2 minutes. 
- Add tomato sauce and water and bring to a boil, skimming any scum that accumulates on top.  
- Lower heat, cover, and cook for about 15 to 20 minutes or until chicken is cooked.  
- Add potatoes and cook until tender. 
- Add chorizo de bilbao, garbanzo beans, and bananas. Cook until heated through.  
- Add green beans and napa cabbage and cook for another 2 to 3 minutes.  
- Add pechay and cook for about 1 minute or until vegetables are tender yet crisp. Serve hot. 
- Season with salt and pepper to taste.