Homemade Sweet and Sour Sauce

Heat the neutral oil in a small stainless steel or other non-reactive saucepan over medium-low heat. Add the ginger slice and star anise, and cook for about 1 minute, until the ginger is lightly caramelized and fragrant.

Stir in the tomato paste and cook for 1 to 2 minutes, stirring constantly, until it darkens slightly and smells rich and sweet. Do not let the tomato paste or spices burn.

Add the sugar, water, white vinegar, and soy sauce. Stir until the sugar dissolves completely, then add the optional fruit juice or syrup if using. Bring the mixture to a gentle simmer.

Lower the heat and simmer for about 10 minutes, or until the sauce reduces slightly and lightly coats the back of a spoon. Remove and discard the ginger and star anise.

Use the sauce as is for stir-fries, or let it cool and store it for later. If you want a thicker dipping sauce, whisk the cornstarch with 2 tablespoons water, then add the slurry a little at a time while the sauce simmers, stirring until it reaches your preferred consistency.