Hull the strawberries and roughly dice. Put all of the ingredients in a small-medium saucepan and put on a medium heat. Stir as it heats to dissolve the sugar and break up the fruit a little as they soften. As it cooks, prepare your jar/jars - either warm in a low over a few minutes or submerge in boiling water to sterilize. Take care using tongs/gloves to handle as you remove.
Bring the jam to a simmer, reduce the heat a little and simmer for approximately 15 minutes (or longer, as needed), stirring occasionally. It should become darker in color and thicker - when you stir a spoon through, it will take a bit longer to close in behind.
Remove the pan from the heat, allow to cool a minute or two then skim off any foam. Transfer to your prepared clean jar(s) and put lid on while still hot. Leave to cool.
Video
Notes
One quantity of this recipe makes a little under 1 cup or an 8oz (236g) jar.