Line a loaf pan with Saran Wrap, making sure there are no holes and then spray the Saran Wrap with oil.
In a bowl, add your 1/2 cup cold water and sprinkle the gelatin on top, mix once, then set aside.
Heat your next 2/3 cup of water in the microwave until very hot/boiling or in a kettle. Pour the hot water into the cold gelatin mixture and mix.
Add your flavoured drink mix and stir until dissolved or combined, taste and add a touch more if needed. You want them sweet like candies but remember they will also have a sugar coating!
Pour this warm mixture into the lined loaf pan and then carefully place the pan flat in the fridge to set overnight or ~6 hours.
Place a large piece of parchment or wax paper on your counter and flip the jell-o onto it.
Slice the sugar free gummy into long rectangles, then squares using a pizza cutter or sharp knife.
In a small bowl, mix together your sweetener and citric acid.
Sprinkle this over the gummies and toss them together just before serving, enjoy your Keto Sugar Free Sour Gummies!