1. Ingredients: tomatoes, pineapple, lemon, rock sugar, white vinegar.

2. Pineapple soaked in salted water and cut into small pieces, tomatoes cut into small pieces and then salted and poured off the excess water reserve.

3. Put the tomatoes and pineapple in the blender into a pulp with rock sugar, and then put the voltage pot to cook for 30 minutes.

4. Juice the lemon and prepare a little cornstarch.

5. Add the lemon juice and cornstarch to the cooked jam and mix well.

6. Slowly continue to simmer until the jam is bubbly.