No-Bake Blackberry Oreo Tart

1. Stage

In a large bowl, mix Oreos, butter, and 1/4 teaspoon salt. Using the bottom of a measuring cup, press Oreo mixture into the bottom and up sides of an 9" tart pan. Freeze until chilled, about 20 minutes.

2. Stage

Meanwhile, in a small saucepan over medium heat, cook gelatin and 3 tablespoons water, whisking frequently, just until gelatin dissolves, about 1 minute. Let cool slightly.

3. Stage

In a blender, blend 15 ounces blackberries into a smooth puree. Strain through a fine-mesh sieve into a medium bowl (you should have about 1 1/2 cups puree). Set aside 1 tablespoon puree for topping. Add orange juice, gelatin, and remaining 1/4 teaspoon salt to remaining blackberry puree and stir to combine.

4. Stage

In the large bowl of a stand mixer fitted with the whisk attachment (or in a large bowl using a handheld mixer), beat cream on medium-high speed until stiff peaks form. Slowly add condensed milk and beat until combined. Set aside 3 ounces cream for topping. With the mixer on low speed, add mascarpone and blackberry mixture and beat until incorporated and no white streaks remain.

5. Stage

Pour filling into Oreo crust. Refrigerate at least 1 hour or up to 2.

6. Stage

In a medium bowl, fold reserved 1 tablespoon blackberry puree into reserved 5 ounces whipped cream just until there are solid streaks of both blackberry and whipped cream visible.

7. Stage

Dollop center of tart with whipped cream. Cut half of remaining 2 ounces blackberries in half. Top cream with halved and whole blackberries and mini Oreos (if using).