Preheat oven to 350°F and line an 8x8 baking pan with parchment paper.

For the cake: Crush graham crackers (1 cup/8 full sheets/120g) in a food processor or in a zip-top bag with a rolling pin and place in a place in a medium size bowl.

Add the all-purpose flour (¼ cup/31g), ground cinnamon (1 teaspoon), baking powder (1 teaspoon) and kosher salt (¼ teaspoon) to the graham cracker crumbs and mix to combine. Set aside.

In a stand mixer with the paddle attachment or with a handheld mixer, cream the unsalted butter (6 tablespoons/85g) and granulated sugar (⅓ cup/67g) on medium-high (speed 6 on a KitchenAid) until light and fluffy, about 3-4 minutes.

Now add one large egg and mix on medium (speed 4) until combined, about 30-60 seconds. Then scrape up and down the bowl and add the remaining large egg and vanilla (1 teaspoon) and mix on medium until combined, about 30-60 seconds more. The batter may look a bit curdled here.

Next add half of the dry ingredients and mix on low (speed stir) until mostly combined. Then add the sour cream (¼ cup/60g) and continuing mixing on low about 30 seconds. Stop and scrape up and down the bowl and then add the remaining dry ingredients; mixing on low until just a few streaks of dry ingredients remain. Use a spatula to finish mixing and pour the batter into the prepared pan and smooth into an even layer. The batter is thick and I like to use an off-set spatula to smooth it.

Bake about 20 minutes, or until a toothpick inserted in the middle comes out with just a few moist crumbs. Allow the cake to cool completely in the pan on a wire cooling rack before frosting.

For the stabilized whipped cream frosting: beat the cream cheese (2 tablespoons/28g - does not need to be room temperature), confectioners' sugar (½ cup/60g) and vanilla (1 teaspoon) on low until combined, then increase speed to medium with a handheld mixer or in a stand mixer (speed 4) with the whisk attachment until smooth. This may take a couple minutes, the mix is very dry and clumpy to start and seems like it won't come together, but it will.

Now add the cold heavy cream (½ cup/120mL) and mix on low until combined. Then turn the speed up to high and whip until stiff peaks, about 2 - 3 minutes more.

Spoon the frosting on top of the cooled cake and spread to cover the top. Garnish with graham cracker crumbs, if desired.