Sterilize your jars by boiling a large pot full of water. Place the jars inside and simmer until you need them. For lids, boil water in a kettle and pour into a large bowl. Soak lids in hot water.
Rinse strawberries under cold water and remove leaves. Add them to a large pan, followed by the sugar.
Slice the vanilla pod open lengthwise and take out the seeds. Add the vanilla pod to the pan and mash the ingredients together until only a few chunky pieces of strawberry remain.
Place pan on a stovetop and turn up the heat until the strawberry mixture starts to boil. Once it boils, reduce heat to low and simmer for 5 minutes. Remove from heat; scoop out any foam forming at the top and let mixture sit for 15 minutes.
Pick the sterilizing jars and lids out of the pot with long tongs. Spoon the strawberry jam into jars and close lids tightly. Refrigerate until chilled and serve.