One empty soda stream syrup bottle with cap (optional)
a 16.9 oz bottle of water
a 4 oz bottle of your extract
9 cups of slenda or equivalant (I'm not sure if I can get that much sugar disolved into the water)
Measure, pour out, 4 oz of water (waste)
Dump the remaining water into a small sauce pan.
Bring the water up to a light boil.
Slowly add in the 9 cups of slenda.
Once the splenda is completely disolved, remove from heat, add and stir in your 4oz of extract. Once cool pour solution into an empty soda stream syrup bottle. Once the solution is cool, add 2 oz (a full cap - not to the line soda stream says to add) per your 1 liter bottle.
After that simply enjoy.