This was delicious, the flavor is a bit light and not too sweet, but very tasty and very simple, provided you have a green apple syrup.
For one gallon:
10 ozs (1 1/4 cups) Monin Green Apple syrup,
3/4 cup brown sugar
1 tsp cinnamon
1 gallon carbonated water.
For one 12 oz bottle:
1/8 cup green apple syrup
1 Tbsp brown sugar
dash of cinnamon
10-11 ozs carbonated water.
Bring the three flavor ingredients just to boiling in a saucepan while stirring then remove from heat to get a thick syrup. Chill then add to carbonated water. Yes, it's that simple. In the future, I'd like to try and make this with Granny Smith apples, but that will be for another time. For now, I'm going to add a scoop of ice cream and enjoy a la mode!
Other green apple syrups can be substituted. The recommendation from Monin was 2 oz syrup to 10 oz carbonated water, so I cut that in half and made up for the reduced sweetness with the other flavors. I'd imagine following recommendations from a syrup such as Torani, then baking down to account for other flavors would be similar and work just as well.
I like the flexibility of this homemade recipe, because it's so easy to do by the glass or single bottle. I can easily whip this up in a few minutes, or keep to small batches if I know my keg is close to empty and I won't have enough carbed water for a larger batch. Just be sure that if you're bottling you should boil first, even if the simplicity is enticing enough not to, you want to make sure you don't have anything wild start to ferment in it. This is obviously less important for single servings that won't sit for long periods of time.