To make the peach nectar,

1. In a medium saucepan over medium heat, fill the pan halfway with water. Cut an x n the bottom of each peach to make the fruit easier to peel after blanching. 
2. Fill a medium bowl with cold water and fill it with a handful of ice, set aside.
3. When the water comes to a boil, place the peaches in the water for a few minutes using a slotted spoon or tongs, and transfer the peaches to the ice water to stop the cooking process.
4. After 2-3 minutes peel off the peach skin and cut each peach in half. Reserve 1-2 peaches for garnish by holding them in a container with water and 1 teaspoon of lemon juice to keep them from turning brown. Cut the other peach halves into large chunks.
5. In a blender, add the peaches and 2 cups of water and process until smooth.
6. Strain the peach liquid through a strainer to remove some of the pulp.
7. Rinse out the medium saucepan and return it to the stovetop. 
8. Add the peach juice, 2 cups water, 3 tablespoons lemon juice, 3/4 cup sugar, and 1/2 teaspoon kosher salt, and bring the liquid to a boil to melt the sugar. Let the peach nectar cool and transfer it to an airtight container in the refrigerator. 

To make the vanilla simple syrup

1. In a small saucepan over medium heat, combine the water, sugar, and vanilla extract. Bring the ingredients to a simmer and cook until the sugar has dissolved, stirring occasionally for about 3-5 minutes. Remove the syrup from the heat and cool to room temperature. Store in an airtight container for up to a month.

To make the Peaches and Cream Mocktail

1. In a half-gallon pitcher, combine 1 quart peach nectar with 1/3 cup vanilla syrup and 1-liter club soda. 
2. Slice 2 of the reserved peaches into small pieces and muddle the fruit at the bottom of the drink. Stir and taste the mocktail. If you want it sweeter, add an additional teaspoon of vanilla simple syrup to taste. Add crushed ice and garnish the glasses with a slice of reserved peach and a mint leaf.