In a pressure cooker, add 500 gm chopped tomatoes, sliced onions, garlic cloves, and grated ginger. Add the water and close the pressure cooker. Keep the heat on high, and at the first whistle, lower heat to low and cook for 15 minutes. Take it off the heat and open the cooker when pressure subsides. Blend the veggies to a fine puree and then strain out the pulp. Cook the pulp now. Keep the heat on high and let the pulp come to a boil. Now, reduce heat to medium and add the sugar. Keep stirring until the sugar dissolves. Let the pulp cook while you prepare an extract of the Khushis’s Ketchup Masala Mix, Khushis’s garam masala & Khushi’s red chilli powder, in water, on another burner. When the extract is ready, strain it directly into the pulp and mix. Cook the tomato pulp until it becomes thicker. Add the vinegar now and mix well. Cook the tomato pulp for about 5–7 minutes on medium heat until it gets to a sauce-like consistency. Do a plate to check there is no extra water remaining in the sauce. Now put off the heat and mix in the salt. Let the tomato sauce cool down completely; then store it in a dry, sterilized bottle. Chilly & salt to taste.