Strawberry-rhubarb icebox cake with pistachio brittle is an epic make-ahead dessert

Ingredients

Strawberry-Rhubarb Jam

• 1 1/2 pounds strawberries, hulled and quartered
• 1 pound red ripe rhubarb, leaves trimmed and discarded, thinly sliced
• 1 1/2 cups granulated sugar
• 1 pinch kosher salt
• 3 wide strips orange zest
• 1 teaspoon freshly squeezed lemon juice, plus more if necessary

Icebox Cake, Pistachio Brittle, and Assembly

• 8 ounces mascarpone or plain whole-milk Greek yogurt, room temperature
• 1 cup granulated sugar
• 1 teaspoon finely grated lemon zest
• 1/2 vanilla bean pod, split and seeds scraped
• 2 1/2 cups heavy cream, chilled
• 48 Biscoff cookies or ginger snaps, or 12 sheets graham crackers
• 1/2 pound strawberries, hulled and quartered
• 3/4 cup raw shelled pistachios
• 1/4 cup raw pine nuts
• 1/4 cup honey
• 1/2 teaspoon kosher salt
• 1/4 cup freeze-dried strawberries, lightly crushed

Directions

Strawberry-Rhubarb Jam

1. In a large skillet and off the heat, stir strawberries, rhubarb, sugar, and a pinch of salt until strawberries and rhubarb are coated in sugar. 
2. Cook this mixture over medium heat, stirring occasionally and skimming foam off the top, until strawberries and rhubarb are very tender and sauce is very thick and jammy, 16 to 20 minutes. 
3. Remove from heat and stir in orange zest and lemon juice. Set aside until cool, then cover and chill.

Icebox Cake, Pistachio Brittle, and Assembly

1. Line a 9x5" loaf pan with plastic wrap, leaving overhang on all sides. 
2. In a large bowl and using an electric mixer on medium-high speed, beat mascarpone, sugar, lemon zest and vanilla seeds until fluffy, about 4 minutes. Reduce speed to low and gradually add in heavy cream. Increase speed to medium as mixture thickens, and continue to beat until medium peaks form. 
3. Using a small offset spatula, evenly spread 1 cup of mascarpone cream over bottom of prepared pan. Dollop 1/2 cup jam over top, then using a knife or toothpick, swirl the jam into the cream layer to make a marbled layer. 
4. Arrange 1/2 cup quartered strawberries evenly over marbled cream. Place a single layer of cookies over strawberries, breaking as needed to fit and pushing the berries into the cream. 
5. Repeat layering process 3 more times, creating 4 layers total and ending with the cookies. 
6. Cover with plastic wrap; freeze at least 6 hours. Cover and chill any remaining jam until ready to serve cake.
7. Meanwhile, make the brittle. Arrange a rack in center of oven; preheat to 350°F. 
8. In a medium bowl, toss pistachios, pine nuts, honey, and salt. Scrape onto a silpat or parchment-lined rimmed baking sheet and spread in a single layer. 
9. Bake brittle until pistachios are golden brown and honey is bubbly, 15 to 20 minutes. Remove from oven and immediately sprinkle with freeze-dried strawberries, lightly pressing them into the cooling brittle to adhere. 
10. Let cool until fully hardened, then break up into small pieces; discard any dark brown, bitter pieces.
11. After it has fully chilled, uncover cake and invert pan onto a platter. Using the plastic overhang to help you, unmold cake; peel off plastic.
12. Slice cake and serve with brittle and remaining jam spooned over.