Homemade Strawberry Jam and Cookies

Strawberry jam:
2 pack strawberries (420 gram)
70 gram - 96 gram granulated sugar (1/2 or 2/3 x 1/3 amount of the strawberries, as you prefer)
1 - 1.5 quarter lemon juice and zest

1. Slice strawberries half
2. Add sugar into strawberries in a bowl and mix them well
3. Wrap the strawberries in a bowl and leave it in the fridge overnight
4. Simmer the strawberries in a middle-sized pot at a low heat for about15 minutes