Rinse the strawberries quickly with salt water when rinsing them after picking the top of the strawberries are washed in running water. Cut the big straw into two pieces. Strawberries have a thin skin that is easy to spoil and soft pulp, so it is better to wash them quickly in running water.

Prepare a large amount of sugar. The strawberry jam ratio is about 2 strawberries to 1 sugar. Add more sugar if you're going to leave it for a long time.

As it can boil over, put strawberries and sugar in a large bowl and leave it at room temperature for about an hour until the sugar melts.

Divide the lemon into four pieces and use only three. Lemon helps the jam to be jellyized well, and it plays a role in making the jam color more refined.

Add lemon juice to strawberries mixed with sugar.

Put it in a pot and when it boils up over high heat, reduce the heat to medium and cook it occasionally for more than an hour with the lid open. At this time, you have to remove the bubbles that start to boil to create a clean taste of jam.

Cover with plastic wrap and make a hole with a toothpick.

Microwave it for 10 minutes, 2 or 3 times. If the jam has a certain concentration and a clear feeling, and a fine light appears, try dropping it in cold water. At this time, if it does not spread and remains as a lump, it can be considered moderately boiled.

The jam is put in a sterilized bottle when it is hot. If you quickly close the lid and cool it upside down, you don't have to go through a separate disinfection process. The bottle used at this time is sufficiently disinfected in boiling water or a steamer and used while the water is removed.