Add all ingredients, except the brown sugar, into a blender.
Blend on high for 30 seconds to 1 minute. Mixture should be mostly smooth. Transfer ketchup to a small sauce pot and stir in brown sugar.
Bring mixture to a boil over medium-high heat, stirring occasionally. Do not walk away or leave unattended!
Once ketchup comes to a boil, give it a good stir and reduce heat to medium-low. Cover and let simmer for 30 minutes. Be sure to stir every 5-8 minutes. Watch carefully! If it starts to bubble over lower heat.
After 30 minutes, ketchup should have thickened, darken in color,and reduced by at least 1/3. It should look very similar to ketchup!
Carefully taste ketchup and adjust sweetness and seasoning if needed.
Let cool for at least 30 minutes. Transfer ketchup into a container or jar and then place in the fridge to cool completely.
Let cool in fridge at least 1-2 hours before serving for best flavor!
Serve with fries & enjoy!