1. Add ice to a mixing glass.
2. Squeeze the Cara Cara oranges over the ice.
3. Add the vodka, lemon simple, and Cointreau.
4. Stir the ingredients together and then use a Hawthorne strainer to pour the cocktail over ice in a rocks glass.
5. Top with club soda.
6. Add a dehydrated orange slice to the rim of the glass.

For the lemon simple syrup:

1.  In a small saucepan, bring the water and sugar to a boil, stirring until the sugar is dissolved.
2. Remove the saucepan from the heat.
3. Add the zest from 1 lemon, the juice from both lemons, and then add 2 halves of the non-zested lemons into the liquid.
4. Allow the syrup to come to room temperature.
5. Once the syrup is completely cooled, strain using a fine mesh strainer into a container. While straining, do not press on the lemons.
6. Refrigerate. This lemon simple syrup will last up to 2 weeks as is in the refrigerator, or if you add a tablespoon of vodka or rum, it will last longer.