In a large pot, put the crabs, 3 cups water and 1 tbsp salt and boil for 20 minutes or until crabs are bright orange in color. When cooked, put aside and let it cool down then cut each crab in to two parts.
In a large frying pan, heat cooking oil and saute garlic and onion until onion is translucent.
Add the crabs and stir, let simmer for 5 minutes and cover the pan.
Add the tomato sauce and stir, add sugar, chili flakes, paprika, salt and pepper then stir everything then cover the pan again and simmer for 10 minutes.
Taste for sweetness, saltiness or spiciness. Also check for the thickness of the sauce making sure there is enough but not too much.
Put in a serving plate and enjoy! Bon Appetit.