Line a 13x9x2 inch pan with parchment paper or foil. Coat lightly with nonstick spray. Bring the 1.5 cups of water to a boil and add the oak chips. Remove from heat and steep covered 30 minutes.

Strain thoroughly through a paper towel lined mesh strainer. Measure a 1/2 cup of the oak water into a bowl and chill until very cold. Measure another 1/2 cup of it into a heavy medium saucepan. Discard extra or save for another use.

Once the oak water is chilled, pour it into the bowl of a stand mixer fitted with whisk attachment. Sprinkle gelatin over water. Let stand until gelatin softens and absorbs water, at least 15 minutes.

Combine 2 cups sugar, corn syrup, and salt with the oak water in the saucepan. Stir over medium-low heat until sugar dissolves. Attach a candy thermometer to side of pan. Increase heat and bring syrup to boil. Boil, without stirring, until syrup reaches 235-240º F, about 8 minutes.

With mixer running at low speed, slowly pour hot syrup into gelatin mixture in thin stream down side of bowl (avoid pouring syrup onto whisk, as it may splash). Gradually increase speed to high and beat until mixture is very thick, about 15 minutes. Add in the vanilla extract if using and beat about 30 seconds longer. It will be voluminous & white, begin to pull away from the sides of the bowl, and will fall very slowly in a thick ribbon when the whisk is lifted when done.Scrape marshmallow mixture into prepared pan with a wet spatula (or you can coat spatula lightly w/ non-stick spray), work quickly as it gets harder to work with if it sits. And by harder I mean almost impossibly stringy and sticky. Smooth top with wet spatula. Let stand uncovered at room temperature until set, about 2-4 hours or over night. (note: if not toasting them you can then mix 1/2 cup corn starch and 1/2 cup powdered sugar, dust the top with the mix, turn them out, slice into desired size with a wet knife, and then toss the individuals with the powdered coating and store in an airtight container up to a week at room temperature)

Put rack in highest position in oven. Turn broiler on high.

Turn marshmallows out of parchment or foil into the baking pan. Place directly under the broiler for 30 seconds – 1 minute. Sometimes it catches fire a bit. This is fine, just be careful and blow it out. If you like yours less charred (I always liked to set my marshmallows on fire as a kid…) place the rack a little lower and watch the marshmallow until it’s browned to your liking. I remove it, stir the char/toasted crust into the marshmallow, and then repeat for maximum toasty charred bits. Toast them to your liking.

Place a generous dollop of charred marshmallow on to one graham cracker, top with another. Repeat with all the graham crackers and marshmallow fluff.

Melt chocolate chips in a microwave safe bowl in 30 second intervals, stirring in between. Dunk one side of s’mores into chocolate and place on a wax paper lined baking sheet. They’re messy. They’re supposed to be! Either eat gooey and melty or place in fridge for a few minutes to let the chocolate harden. Leftovers can be individually wrapped once chilled and stored in the fridge and be either eaten straight from the fridge or, for a softer texture, allow to sit out for about ten minutes before eating.