Place the orange zest, lemon zest, and sugar in the bowl of a food processor fitted with the blade attachment. Pulse several times, until the sugar and zest are combined and the texture is moist and sandy.
Place the sugar, orange juice, lemon juice, egg yolks and salt into a medium saucepan and whisk until very smooth. Cook over medium low heat, stirring constantly and scraping the sides of the saucepan, until thickened, about 8 minutes.
Bring the mixture to a simmer and cook for an additional 2 minutes, stirring constantly.
Remove the pan from the heat and stir in the butter one tablespoon at a time.
Divide the curd among the mason jars, filling them so they are about ½-inch from full. Screw on the lids.
Pour 2 cups of water into the inner pot of the COSORI Pressure Cooker, place the steamer rack inside, then position the mason jars onto the steamer rack.
Place the lid onto the pressure cooker and slide the vent switch to Seal.
Select the Pressure function on the COSORI Pressure Cooker, adjust pressure to high and time to 10 minutes, then press Start.
Release pressure quickly by sliding the vent switch to Vent.
Open the lid carefully and lift out the jars using a towel or potholder. Let them cool to room temperature, then chill in the refrigerator for 6 hours or overnight.
Beat the heavy cream to stiff peaks, then fold 1 jar of the orange curd. Cover and chill in the refrigerator for 6 hours or overnight.
Place the graham crackers and hazelnuts in the bowl of the food processor and pulse until finely chopped, then stir in the melted butter. Place the mixture onto a sheet pan and toast in the oven at 350°F for 10 minutes, or until lightly browned on top.
Divide the crumble among 4 shallow glass bowls, then top each with 2 tablespoons of the curd and divide the whipped mousse evenly among the bowls. Garnish with more of the crumble, mint leaves, and berries, then serve.