½tspcoarse Kosher salt(if using table salt, use half the amount)
½cupcold, unsalted butter
1tbspmilk or cold water
Filling
⅓lbrhubarb,chopped
⅓lbstrawberries,hulled and chopped
¾cupgranulated sugar
2tbspwater
12ozcream cheese,softened to room temperature
1 ½tspvanilla extract
1 ½cupscold heavy whipping cream
Instructions
Crust
Lightly spray the bottom and sides of your tart pan with non-stick baking spray.
In a food processor, pulse the flour, powdered sugar, cocoa powder and salt until combined. With the processor running, drop in the cold butter, 1 tablespoon at a time. Add the milk, and pulse just until the crumbs come together into a ball of dough.You can also make the dough in a bowl, and use a pastry cutter to cut the butter into the dry ingredients. Then use your hands to work the butter and milk into the crumbs until it comes together into a ball of dough.
Lay a piece of parchment paper on the counter, and dust with flour. Dust the ball of dough with flour, then roll out into a rectangular shape, large enough to fit into your tart pan. Use more flour as needed to make sure the dough doesn't stick to the paper or your rolling pin.
Use the paper to transfer the dough to the pan, by turning the dough over onto the pan, then peeling off the paper. Press the dough firmly against the bottom and sides of the pan, then trim the dough evenly with the top of the pan.
Freeze the crust for 30 minutes.
Preheat the oven to 350.
Lightly spray a piece of aluminum foil with non-stick baking spray. Fit the foil, greased side down, into the frozen crust. Fill the foil with pie weights or dried beans.
Bake the crust, covered with the foil and weights, for 25 minutes.
Remove the pan from the oven, scoop out the weights, and peel off the foil. Return the pan to the oven and bake for 10-12 more minutes, until the crust is cooked through.
Set aside to cool completely.
Filling
In a saucepan, combine the rhubarb, strawberries, sugar and water. Bring to a boil over medium heat, then simmer until the rhubarb is softened and can be easily mashed.
Remove from the heat, and puree the strawberry rhubarb mixture in a blender or food processor until smooth.
Refrigerate the puree until well chilled. You can speed up the chilling process by spreading the puree out onto a plate instead of chilling it in a bowl.
In a bowl, use an electric mixer to beat the cream cheese for 1 minute until smooth. Beat in the chilled strawberry rhubarb puree and the vanilla extract.
Gradually stream in the cold heavy whipping cream, and beat until the mixture is thick enough to hold its shape.
Spread the filling into the cooled crust, or fill a piping bag to pipe it in more decoratively.
Refrigerate several hours, until chilled and set.
To serve, remove the sides of the pan, and cut the tart into slices.