Ingredients
Method
Start by making the pastry cream for the creme diplomat
- In a medium sized heat safe bowl, whisk together the egg yolks and cornstarch. It should be a very thick consistency at first but as you keep whisking it should come together.
- In a large saucepan, whisk together the whole milk, granulated sugar, nutmeg, cinnamon, cloves, ginger, and rum over medium heat. Bring the mixture to a simmer, whisking occasionally. Once simmering, remove roughly ½ cup of the milk mixture and slowly stream it into the egg yolks, whisking constantly. Then, stream this mixture through a sieve back into the saucepan with the remaining milk. Continue to cook on medium high heat until the mixture starts to bubble on top. Once bubbling, let the custard cook for 30 seconds without stirring. Then, stir it again before letting it cook untouched for another 30 seconds. Remove the saucepan from the heat and stir in the butter and vanilla bean paste. The pastry cream should be a thick pudding like consistency at this point. Let the cream cool in the saucepan for 10 minutes before transferring to a heat proof mixing bowl. Cover with cling wrap, making sure it touches the surface of the custard. Let the custard chill in the refrigerator for 4 hours while we prepare the rest of the tart.
Make the crust
- In a large bowl, toss together the flour and salt. Then, using a pastry cutter, cut in the cold cubed butter until it forms small pea sized crumbles. Add the buttermilk and use a spatula or a wooden spoon to bring the dough together. You may need to add a little more buttermilk, but it's okay if it has some dry spots. It shouldn't be sticky.
- Place the dough onto a lightly floured work surface. Roll it out into a 12 inch circle. Carefully transfer that to a 9 inch tart pan. Use your finger to press it into the pans bottom and sides. Cut excess off of the edges if necessary. Place in the refrigerator to firm up for 40 minutes.
While the crust chills, make the frangipane filling
- Grind up the almonds and rosemary in a food processor until they reach a texture slightly coarser than almond flour. Set aside.
- In a large bowl using either a stand or hand mixer fitted with a paddle attachment, cream together the butter and brown sugar until fluffy and smooth. Add the eggs one at a time, mixing after each. Mix in the egg yolk, vanilla extract, and almond extract. Add the almond flour, salt, ginger, and the ground up almonds, mixing until combined. It should be a somewhat pasty consistency. Set aside.
- Preheat the oven to 375℉. Spread the filling evenly into the chilled pie crust. Place in the refrigerator for 20 minutes.
- Bake the chilled tart for 30 minutes or until the top is golden brown. Allow the tart to cool completely before topping with the cream.
Make the sugared blackberries and rosemary
- Place ¾ cup of sugar in a large shallow bowl. Set aside. In a medium sized saucepan set over medium heat, mix together 1 cup of sugar and the water. Cook until the sugar has completely dissolved. Once dissolved, add the blackberries to the syrup and toss them to make sure they are all evenly coated before pouring the mixture through a sieve into a bowl. The syrup should now be in a bowl and the blackberries should be in the sieve. You don't want the blackberries to sit in the syrup for longer than 30 seconds. Toss the syrup soaked blackberries in the granulated sugar in the shallow bowl until evenly combined. Pour them onto a baking sheet lined with parchment paper to dry. Dip the rosemary sprigs in the sugar syrup until evenly coated, and then toss in the sugar on the baking sheet. Let the rosemary and blackberries dry before using them on the tart.
Finish the creme diplomat
- Once the custard has chilled, make the stabilized whipped cream. Place the cold water in a small bowl and sprinkle the gelatin on top. Let the mixture sit for 5 minutes, or until the gelatin absorbs the water and is thick. Then microwave the mixture in 5 second increments until you are left with a thick, clear, syrupy mixture. Set aside to cool.
- In a large mixing bowl using a hand or stand mixer fitted with a whisk attachment, whip the cream on high speed to soft peaks. Soft peaks means when you lift the whisk out of the bowl, the cream should just barely hold it's shape. Turn the mixer down to low speed and very slowly stream in the cooled gelatin mixture. Then turn the speed up to high and whip to stiff peaks. Make sure you don't over whip this!
- Remove the custard from the fridge and whisk until smooth again. It will be very thick. Carefully fold the custard into the stabilized whipped cream until just combined. Scoop the creme diplomat into a large piping bag fitted with a large round tip. Pipe little dollops all around the cooled tart. Top with the sugared blackberries and rosemary. Let the tart chill for 30 minutes before slicing and serving. Tart stays fresh covered in the refrigerator for up to 5 days.