Crust 

1. Add your Biscoff cookies, brown sugar, salt, and melted butter to your food processor. Grind cookies [in two batches if needed for a smaller food processor] into a fine, crumb-like texture, which will resemble wet sand.
2. Line your springform pan with a 9-inch round of parchment paper before using the base of a round glass to evenly press the crumb mixture into the bottom and slightly up the sides of the pan.
3. Place in the freezer or refrigerator to firm up as you make the filling. 

Mango Filling

1. Add mango chunks to a small pot on the stove, over medium heat. Let cook for 5 minutes, stirring every minute or so as mango juices release.
2. Add lemon juice, sugar, and salt to pot and let it cook over medium-low heat for 16-20 more minutes, bubbling gently. Mango will become very soft, similar to the texture of cooked apples. 
3. Let mango cool for a few minutes before adding to a food processor, blender, or using an immersion blender in the pot. If you’d like to remove the pulp, put your mango filling through a fine mesh sieve, reserving the smooth pureed mango.

Mascarpone Filling & Whipped Mango Topping

1. Using a chilled mixing bowl, beat cold mascarpone cheese, heavy cream, powdered sugar, and vanilla extract on a slow speed initially for 30 seconds. Increase speed to medium for 1 more minute as soft peaks form.
2. Then, add cooled mango puree and increase to medium-high speed for another minute. 
3. Evenly spread the mango mousse filling into the prepared crust. Smooth over with a spatula.
4. Refrigerate mousse cake for at least 6 hours, or until set.
5. Once set, remove it from the refrigerator and gently slide it from the springform pan onto serving dish.
6. As close to serving time as possible, add powdered sugar, cold heavy cream, and freeze dried mango powder to a cold mixing bowl, mixing on medium high speed until stiff peaks have formed (generally 1-2 minutes) .
7. Put in piping bag fitted with tip of your choice and cover mango mousse cake. Serve, and enjoy!