Heat sous vide bath to 176°F (80°C).
To remove seeds from the vanilla bean: run the tip of a paring knife lengthwise down the center of the bean to expose the seeds inside and split the bean into two pieces. Place the halves, skin side down on a cutting board. Using the dull edge of a knife, run the knife down the center of each pod to remove the seeds.
Add vanilla seeds and sugar to a small bowl and combine thoroughly with your fingertips so that no clumps remain.
Note: the empty vanilla pods can be utilized to infuse various liquids or add to a jar of sugar to create vanilla-scented sugar.
In a large bowl, whisk egg yolks, vanilla sugar and salt until well combined. Continue whisking as you slowly incorporate the heavy cream. Strain the mixture into a large clean bowl and rest 20 minutes. This ensures that all bubbles will have time to rise to the surface and dissipate. Yields 3 1/2-cups.
Fill each mason jar with a generous 1/4-cup of the liquid; reserving the remaining 2-cups liquid for the Vanilla Ice Cream recipe. Close each jar so the lid is fingertip tight. When the sous vide bath is at proper temperature, use tongs to submerge each jar into the bath in an upright position. Do not be alarmed if bubbles rise to the surface of the water bath, as this is air escaping from the jars. Sous vide for 1 hour.
Using tongs, remove mason jars from the water bath and place on countertop. After 15 minutes, remove the lids to ensure that condensation does not develop and then allow the jars to cool to the touch. When the jars have completely cooled, about 35 to 45 minutes, add and tighten the lids. Reserve jars in refrigerator for at least 4 hours and up to 1-week, before service.
Fill an ice cream/sorbet maker or Paco Jet* cylinder and follow manufacturer's directions to make the vanilla ice cream.
Rinse mint sprigs, pat dry and reserve.
Slice peaches or nectarines into 24 wedges and 12 cubes for plating.
Refrigerate ingredients until serving.
Remove Vanilla Ice Cream from freezer to soften for service. If using a Paco Jet*, pacotize the ice cream reserved in the beaker.
Fill a tall glass with hot water and insert a thin paring knife to warm.
Remove the crème brûlée jars from refrigerator and run the tip of the knife around the edge of each brûlée 3 to 4 times; cleaning the knife with a paper towel after each rotation.
Invert each brûlée onto small individual plates and if necessary, tidy and remold each with a damp finger.
Dust the top of each brûlée with 1/4-teaspoon caster sugar (2nd amount).
Using a kitchen torch, torch each brûlée until the sugar has caramelized and is golden brown.
Add mint and peach wedge garnishes to each plate and serve.