In a large Dutch oven or stock pot, add the chicken drumsticks and cover with water (about 9 cups). Add 1/2 onion, garlic cloves, bay leaves and 1 tsp salt. Cook 25 minutes on medium-high, removing any foam from the top.
While the chicken cooks, make the sauce: in a blender add 3 Roma tomatoes, 1/4 onion, 3 garlic cloves, chicken bouillon, tomato bouillon, cumin and 1 cup water. Blend until smooth and set aside.
After 25 minutes, remove the chicken and set aside. Save the water the chicken cooked in.
In a large deep pan, heat 3 tbsp oil over medium. Once hot, add the fideo pasta and stir into the oil, toasting until golden brown. Add the blended sauce to the toasted fideo.
Add 6 cups of the reserved chicken water. Return the cooked chicken to the pot. Stir in the cilantro and 1 tbsp more chicken bouillon. Add the jalapeno now if using. Taste and adjust salt and pepper.
Reduce to low heat, cover and cook 15 minutes. Serve with tortillas and the optional toppings.