Submerge your canning jars under boiling water for 5 minutes to sterilize.
Make the jam
In a large saucepan over high heat, combine the crushed strawberries, minced jalapeño, lemon juice, and pectin. Add the sugar and stir to dissolve. Bring the mix to a full boil and cook at boil for one minute, then remove from heat.
Preserve your jam
Transfer the jam into your canning jars, leaving 1/4 inch at the top of the jar.
Slide a knife or spatula around the inside of each jar to remove air bubbles. Remove any excess jam from the jar rims with a moist paper towel. Then seal the jars.
Process the jars in a boiling water canner (approximately 10 minutes, follow the canner’s instructions), then remove the jars and allow them to cool for 8 to 10 hours (overnight is a good amount of time).
Store your preservers in a dark, cool environment.