Cut the dried fish into smaller pieces, while removing the bones. Wash and soak in some water just before you start cooking. This will make it easy to blend later.
Heat oil in a pan (use a non-stick pan if you have one) under medium heat.
Add the onions into the oil. Stir until the onion slices are translucent, and just beginning to brown. This will take 10-15 mins.
Remove from heat and allow to cool. In that time, drain the fish and pour into a blender. Prepare the scotch bonnet and garlic. Add into the blender with the tomato puree and ginger root.
Add the onion and the oil into the blender and puree. Pour the blended mixture back into the pot and place on low heat.
Add the dried shrimp, pepper flakes, cloves and a dash of salt.
Allow to simmer gently, while stirring frequently to prevent burning. If it the sauce appears dry, you can add more oil.
The colour will change gradually and by the time the sauce is done, it will be quite dark. This will take around 20 mins.
Allow to cool and keep in a closed container. Refrigerate and use as needed.