Strawberry and Pistachio Mousse Mille Feuilles
For the rough puff pastry, adapted from Michel Roux.
2 1/4 cups (300gr) all purpose flour
1 1/4 cup (300gr) unsalted butter, cold and cut into 1/4-inch cubes
1/2 teaspoon (3gr) salt
1/2 cup (125ml) ice-cold water
Place the flour in a large bowl and make a well in the center. Add the butter and salt right in the well and work them together with the flour, using your fingertips, gradually drawing in more flour into the center. When the butter pieces have reached pea sized pieces and the mixture appears grainy, gradually add the ice water and mix until it is all incorporated. Do not overwork the dough. Roll it into a ball, cover with plastic wrap and refrigerate 20 to 30 minutes.
On a lightly flour work area, roll the dough to an 8×4-inch rectangle. Fold it into three and give it a quarter turn. Roll it into another 8×4-inch rectangle again and fold it in three again. These are the first 2 turns. Cover with plastic wrap and refrigerate again for 30 minutes.
Give the chilled dough 2 more turns, rolling and folding as previously described. The pastry is ready then. Cover with plastic wrap and refrigerate for 30 minutes.
When ready to use, roll the dough to a 1/8- inch (3 mm) thick rectangle and cut out eight 4×2 pieces. Place them on a parchment paper lined baking sheet. Dock the dough with a fork to let the steam out while baking so your rectangles will be evenly puffed. Bake at 350F until golden brown. (if they puff too much, cover with a sheet of parchment paper and place a small baking sheet on top). Let cool completely before filling with the mousses
For the pistachio and strawberry mousse:
8 oz (240gr) mascarpone cheese, at room temperature
1/2 cup (100gr) sugar
1/4 cup (30gr) finely ground raw pistachios
1/2 cup pureed fresh strawberries
1 1/2 cups (375ml) heavy cream, kept cold, divided
In a large bowl, whisk together the mascarpone and sugar until completely smooth. Take half the mixture and place it in another large bowl. Add the pistachios to one of them and mix until incorporated. Add the pureed strawberries to the other mascarpone mixture. In a mixer, whip the heavy cream to stiff peaks. Fold half into the pistachio mascarpone mix and the other half with the strawberry one. The pistachio mousse is probably stifff enough to be used right away but you might have to refrigerate the strawberry one until the mascarpone hardens a bit otherwise it might be too soft to pipe easily. Divide the mixture into piping bags fitted with medium plain tips (I use Ateco pastry tips) (or do the pistachio mousse first, wash your bag and tip and then do the strawberry one). Pipe dots of mousse onto half the puff pastry sheets, alternating the pistachio and strawberry. Top with another sheet of puff pastry and refrigerate at least 30 minutes.