Combine strawberries and Pom juice in a large stock pot and mash the berries roughly with a potato masher.

Cook the mixture on medium heat, covered, for about 10 minutes, being sure to stir frequently.

Add in the sugar, salt, and lemon juice. Attach a thermometer to the pot and continue to heat, uncovered and stirring every few minutes, until temperature hits 220ºF, being sure to skim off any excess foam from the top of the jam as it forms. (This step can take some time. It took about 45 minutes for me to reach the adequate temperature.)

Note: You can also test the consistency of your jam by keeping a spoon next to you in a glass of ice water. To test, pour a small amount of the cooking jam onto the chilled spoon and allow it a minute or two to cool. If the consistency is what you expect it to be, you’re good to go. If not, keep it over the fire a bit longer.

Remove from heat and stir in the vanilla.

Store jam in the fridge or can in a hot water bath using sterilized containers.