Peel and slice carrots into rounds. Set aside.
Add carrots to medium saucepan and add water just to cover. Cook for 10-15 minutes or until soft. Drain.
Puree the cooked carrots - use an immersion blender, regular blender or food processor. Push out any excess water.
Add the pureed carrots back to the medium saucepan, along with the sugar.
Bring to a boil, stirring constantly as it boils for 5-7 minutes. If froth shows on the surface, skim and toss.
Remove from heat, allow to cool slightly, then stir in the lemon zest and juice.
Pour into warm, sterilized jars and scew on the canning lid and ring. Store in the refrigerator and use within 2-3 weeks.