This Coffee Mousse Cheesecake features a thick graham cracker crust with a silky cheesecake layer topped with coffee mousse and whipped cream.
Preheat oven to 350°F.
Stir together ground graham crackers, melted butter, and salt until thoroughly moistened. Transfer to a 9-inch springform pan. Press into an even layer into the bottom and up the sides of pan. Use the flat bottom of a drinking glass or measuring cup to smooth out the crust.
Bake for 10 minutes until crust is set. Use the flat bottom of drinking glass to press down any bits of crust that may have puffed up during baking. Set aside to cool.
Preheat oven to 325°F.
Wrap springform pan in heavy duty foil. Use enough foil to ensure water cannot enter the pan. To be safe, you may want to add two or three layers of foil. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment, beat cream cheese on low speed for about 4 minutes until soft and smooth.
Add sugar and beat on medium speed for about 2 minutes. Add salt, vanilla, and cream. Mix on low until combined.
With the mixer running on low, add eggs one at a time, ensuring each egg is incorporated before adding the next. Scrape down sides of bowl as needed to ensure thorough mixing. Add sour cream and mix until smooth.
Pour cheesecake filling into foil wrapped springform pan. Use a mini offset spatula to spread filling into an even layer.
Place springform pan in a large roasting pan. Meanwhile, bring about 6-8 cups of water to a boil (you may need more water depending on size of roasting pan).
Place roasting pan in the center rack of oven. Pour boiling water into roasting pan until about 1 1/2-inch of springform pan is submerged in water.
Bake cheesecake for 45-50 minutes.
Turn off oven heat. Crack oven door slightly ajar to let the oven and cheesecake cool. Cool cheesecake in oven for 45 minutes. Remove from oven and remove cheesecake from water bath. Let cheesecake sit at room temperature until completely cooled.
*At this point, cheesecake can be covered with foil and stored in the fridge overnight. Coffee mousse layer may be added the following the day.
In a small bowl, mix together gelatin powder and water. Let sit for 5 minutes to bloom gelatin.
Bring milk to a simmer. Stir in espresso powder until dissolved. Remove from heat and stir in vanilla extract. Add in bloomed gelatin. Stir until gelatin has completely dissolved. Pour mixture into a large mixing bowl and set aside.
Place white chocolate in a small bowl. Microwave in 20 second intervals at half power. Stir in between intervals. Continue to heat until chocolate is smooth and melted. Let cool for 5 minutes.
Pour melted white chocolate into coffee milk mixture. Stir to combine until smooth and homogenous.
In another bowl, whip cold heavy cream to soft peaks. Add whipped cream to cooled white chocolate milk mixture in three additions. Fold gently. Fold until there are no longer any white streaks of whipped cream left.
Pour coffee mousse over cooled cheesecake layer. Use a mini offset spatula to spread mousse into an even layer. Cover with foil and place in the fridge to chill for at least 4 hours, overnight is best.
In a large bowl, whip cold heavy cream, powdered sugar, espresso powder, and vanilla to stiff peaks. Transfer whipped cream to a piping bag fitted with a star tip (or plain round tip). Pipe dollops over chilled coffee mousse layer. Alternatively, spread whipped cream over mousse layer.
In a small bowl combine powdered sugar and cocoa powder. Dust over whipped cream topping.