In a medium-sized mixing bowl, combine the water, soda, soy sauce, cornstarch, flour, and brown sugar. Mix well until everything is dissolved and free of lumps.
Transfer in a casserole and cook it over medium heat. Stir continuously until the sauce thickens.
Add in the onion and garlic and simmer it under low heat for another 5 minutes. You can also add red chilies for that sweet spicy taste.
Transfer to a sauce dish or metallic-lined small paper plates for a more traditional feel of eating your favorite street foods. Serve with your favorite fried fish balls, kikiam, kwek kwek, or squid balls.
Recipe by Maputing Cooking at https://maputingcooking.com/recipe/filipino-street-food-fishball-sauce-recipe/