Wash the strawberries, clean, chop and mix with jamming sugar and lemon juice. Let sit for approximately in a saucepan. Then, bring to a boil, reduce heat and simmer till thick, about 4 minutes.
Transfer jam to a sanitized glass jar. Top with a tight fitting canning lid. Place lid side down on the counter for 10 minutes, creating a seal. Once cool, store in a dark place.