Place the egg whites and sea salt in the bowl of standing mixer fitted with a whisk attachment. Place the maple syrup in the medium-sized pan, with the candy thermometer clipped to the side. Make sure the thermometer isn’t touching the bottom of the pan (that can give you a false reading). Turn the heat to medium high and carefully monitor the pan until the maple syrup starts to boil. Turn the heat to medium low and start to stir constantly with a heatproof spatula, to make sure the maple syrup doesn’t boil over. Cook the syrup until it reaches about 260 F, then turn the mixer on to high to whip the eggs. Paying attention to the mixer (and the maple syrup as you don’t want it to boil over) whip the egg whites until soft peaks form. Turn the mixer off and continue to cook the syrup until it reaches 275 F. Turn the heat off, and turn the mixer back on to high speed. Slowly drizzle the hot maple syrup down the side of the bowl, into the egg whites. Don’t pour too fast, or pour in the middle of the bowl, as the whisk attachment will whip the syrup onto the side of the pan and it will immediately harden. Continue until you’ve incorporated all the syrup.
Let the nougat cool a bit while you make the peanut candy crunch by placing the maple syrup, heavy cream, butter and salt in a clean medium-sized pan with the candy thermometer clipped to the side. Turn the heat to medium high and carefully monitor the pan until the liquid starts to boil. Turn the heat to medium and start to stir constantly with a heatproof spatula to make sure the maple syrup doesn’t boil over. Cook until the candy reaches 250 F. Turn the heat off, split the vanilla bean lengthwise and scrape the seeds into the candy and then add the chopped peanuts. Stir to mix in the vanilla and peanuts and then pour over the nougat. Immediately spread with an offset spatula (or butter knife) to cover the nougat. Sprinkle the vanilla salt over the candy. Let cool for 30 minutes then refrigerate (uncovered) for four hours or overnight.