Make the pistachio paste by blending the pistachios and neutral oil in a food processor until completely smooth and glossy, scraping down the sides as needed. The texture should be similar to natural peanut butter.

In a small bowl, sprinkle the gelatin over the cold water and stir together with a spoon. Let the mixture sit for at least 5 minutes to bloom.

In a medium saucepan, combine the heavy cream and milk. Heat over medium until it is steaming

In a separate bowl, whip together the egg yolks and sugar until slightly pale. Slowly pour in about half of the hot cream mixture while whisking constantly to temper the eggs. Then pour everything back into the saucepan

Cook the custard over medium heat, stirring constantly with a spatula, until the mixture thickens slightly and coats the back of a spoon (180°F). Do not let it boil.

Remove from the heat and stir in the bloomed gelatin until fully dissolved. Whisk in the pistachio paste until smooth

Pour into a bowl, cover with plastic wrap pressed directly against the surface, and refrigerate for at least 3 hours.

Whisk flour, baking powder, and salt together.

In another bowl, whisk yolks, brown sugar, oil, and water.

Sift in dry ingredients; whisk until smooth.

In a mixer, whip egg whites + cream of tartar to soft peaks. Gradually stream in sugar; whip to stiff, glossy peaks.

Whisk ⅓ of meringue into yolk mixture to lighten, then fold in the rest gently.

Pour into an ungreased 8” round pan. Bake at 325°F ~30 min, until golden and springy.

Drop pan from 6 inches (helps prevent sinking). Cool completely before releasing.

Cut the cooled cake layer in half

Line the 8” cake round with a piece plastic wrap (the goal is to cover the bottom with long “handles” so you are able to lift up the cake with plastic when it is done)

Place half the cake in the bottom with the cut side up

Place the pistachio cream on top and spread it into an even layer

Top with the remaining cake layer and place in the fridge for 2 hours

In a large bowl, combine the mascarpone cheese and heavy cream. Beat on medium speed until well combined, about 30 seconds.

Add the sugar, salt, vanilla bean paste, and espresso powder. Continue to beat on medium-high speed until soft peaks form, about 1-2 minutes. Do not over mix or the mixture will split. You want to just mix until soft peaks form

Pour the cream over the cooled cake. Spread into an even layer so the top is flat. Cover with a piece of plastic wrap to set for at least 1 hour.

Dust with cocoa powder and serve.