In a large pot, add fish head, tail, and bones, ½ onion, 1 garlic clove, bay leaf, salt and pepper.
Add 10 cups of water.
Cover and bring to a boil.
Reduce heat and let simmer for 15 minutes.
Turn heat off.
Strain to discard bones, onion, garlic, and bay leaf.
Set broth aside until ready to use.
In a blender, add tomatoes, 1 cup water, ½ onion, 1 garlic clove, 1 chipotle pepper, salt.
Blend until smooth.
Set aside.
Heat oil in a large stock pot.
Carefully add the tomato sauce.
(Warning, it will splatter slightly when adding the tomato mixture).
Cook for 2 minutes, stirring constantly.
Add all the homemade fish broth. (Or, water + bouillons, if using)
Add the potatoes, carrots, and bay leaf.
Taste for salt.
Bring to boil.
Add the fish and cook for 3-5 minutes, depending on the thickness of the fish.
Serve in a deep bowl with lime wedges and top with chile de árbol and green onions.
