To make the dough mix flour, baking powder, salt and sugar in a large bowl. Add margarine and rub in using your hands until it resembles a crumble. Add water and mix to form a dough then set aside.
To make the filling add oil to a pan and cook peppers, celery and onion and cook until softened, about 5 minutes.
Add garlic, thyme, oregano and tomato paste and cook for an additional minute or two.
Add flaked salt fish and cook for about 5 minutes. Add water, ketchup and hot pepper and cook on low for an additional 10 minutes until the water has evaporated.
To make the patty divide the dough into 10 equal pieces. Roll into an oblong shape and fill with a spoonful of saltfish filling leaving an inch border around the edges. Fold dough over filling to form an oblong shape and press the ends close with a fork.
Fry in hot oil until golden brown on both sides.
Place on a plate lined with paper towel and allow to cool.
Serve warm.