Whole blanched almonds may be substituted for the blanched, skinned pistachio nuts.
Heat oven to 325 degrees. Bring a medium pot of water to a boil over high heat. Add the pistachio nuts, and blanch for 30 seconds; drain. When nuts are cool enough to handle, remove skins. Spread out on a baking tray, and place in the oven until they are dry but still green in color, 15 to 20 minutes. Remove from oven, and allow to cool. Set aside 1 1/4 cups nuts. Transfer remaining nuts to a food processor, and process until coarsely ground. Place ground nuts and milk in a medium saucepan, and bring to a boil over medium heat. Remove from heat; transfer to a medium bowl; set aside in the refrigerator for 3 hours.
To make the praline: Place a Silpat (a French nonstick baking mat) on a baking tray; set aside. Place 3/4 cup sugar and 1/4 cup water in a small saucepan set over medium heat. Cook, stirring occasionally and brushing down the sides of the pan with water as needed, until sugar is golden in color, about 10 minutes. Add reserved 1 1/4 cups nuts, and stir to combine. Pour mixture onto the prepared baking tray, and allow to cool. Break into pieces, and place in the bowl of a food processor. Pulse until the caramel is coarsely chopped; set aside.
To make the bavarian cream: Fill a bowl with ice and water; set aside. Remove milk-nut mixture from refrigerator, and strain through cheesecloth into a medium saucepan, squeezing all milk from the nuts. Discard nuts. There should be 2 cups strained milk. Bring milk to a simmer over medium-low heat. While milk is heating, whisk egg yolks with remaining cup sugar in a medium bowl, until pale and combined. Pour hot milk slowly into egg mixture, whisking constantly. Return egg-milk mixture to the saucepan, and cook, stirring constantly until it thickens and coats the spoon, 3 to 5 minutes. Do not allow mixture to boil. Remove from heat, and stir in softened gelatin until completely dissolved. Strain mixture into a clean bowl, and set over ice bath, stirring occasionally until mixture is cold. Add kirsch, and stir to combine.
Using an electric mixer, whip heavy cream to soft peaks. Fold whipped cream into egg-milk mixture until just combined. Use immediately.