To make the brine, add water, vinegar, salt and sugar to a medium saucepan over medium-high heat. cool off.
Stir until the salt and sugar are dissolved and bring the mixture to a boil before removing from the heat to cool off.
Meanwhile, pick straight green beans (not the curvy ones) and trim the ends; discard them.
Stack the beans in a mason jar for the right amount. Remove them and wash the jar thoroughly.
In another pot, quickly blanch the green beans in boiling water, about 45 seconds before transferring them to an ice water bath to stop the cooking process. Let them cool completely.
In the clean jar, add garlic, dill and red pepper flakes. Pack the jar with cooled green beans and then pour in the cooled brine, making sure to cover the veggies completely.
Place sterilized lid on then the screw band and transfer to the fridge. Let them sit 2 days before enjoying them.