Prep the mason jar according to jar instructions. 

Once jar is prepped place dill heads in the bottom of the jar and add in the garlic, red pepper flakes and mustard seed. 

Pack jar full of green beans. (Depending on how big the green beans are will determine how many you can get into the jar.) Set Aside. 

The pickling mixture is a 1:1:1 ratio of: water, vinegar and picking salt. Heat the pickling mixture until the salt is dissolved. 

Ladle pickling mixture into jars leaving a 1/2 inch to an inch of head room. 

Seal the jar tight with the lid. 

Place the jar in room temperature water in a large pot. Make sure there is at least 1 inch of water above the lid. Bring to a boil, and boil for 10-15 minutes. Immediately take out and set on a cutting board. 

As the jar cools it should seal. You will likely hear the "pop" noise. If the jar doesn't seal then you will need to refrigerate. 

Let pickle for at least 2 weeks prior to eating. 

Enjoy!