In a large mixing bowl, whip the egg whites to soft peaks.
Stream in 1 tablespoon of sugar while whipping on low speed.
Continue to whip, on high speed, until the stiff peak stage.
Transfer the egg whites to another bowl.
Place the egg yolks in the large mixing bowl, along with ⅓ cup of sugar.
Whip on high speed until the mixture looks pale and fluffy. Set aside.
In a medium mixing bowl, whip half (3/4 cup) of the heavy cream until it holds stiff peaks.
Fold the whipped cream into the yolk mixture.
Fold the mascarpone, pumpkin puree, and spices carefully into the cream and yolk mixture.
Fold the egg whites into the pumpkin mixture, taking care not to deflate the air from the meringue. Refrigerate.
In a small bowl, combine the espresso, bourbon, and vanilla.
Break the savoiardi into thirds, dip each piece in the coffee mixture, and layer in the bottom of your serving glasses/dish.
Top with half the pumpkin mixture.
Layer on the remaining savoiardi, and top with the remaining pumpkin mixture.
Just before serving, whip the remaining (3/4 cup) heavy cream with the remaining tablespoon sugar.
Top the serving glasses/dish with the whipped cream, and dust with ground cinnamon.