Follow the steps in order for the best result.
Heat the oil in a pan over high heat. Add the chopped onions, garlic, and ginger. Sauté until the mixture becomes fragrant, approximately 2 minutes.
Introduce the drained kidney beans, ketchup, and half a cup of water into the pan. Stir well to combine all the ingredients.
Taste the mixture. Typically, the brine from canned beans provides sufficient saltiness, but add salt to your preference if needed.
Cover the pan and reduce heat to a simmer. Allow the beans to simmer until the sauce thickens to your desired consistency, usually about 5-10 minutes, depending on the amount of water used.
Note: North American ketchups may have a more tart and acidic flavor compared to Caribbean varieties. For a more authentic Caribbean flavor, add sugar to the sauce, starting with 1 teaspoon at a time, until you achieve the desired sweetness.