In a medium bowl, whisk together flour and salt until well combined. 

In the bowl of a stand mixer using the paddle attachment, cream the butter until smooth; 2 minutes. Add the Redpath® Organic Granulated Sugar and cream on medium-high speed until mixture is light and fluffy; 5 minutes. Add in the egg yolk and blend until incorporated. Add in the heavy cream and vanilla extract. Cream until well mixed. 

Add in the dry ingredients. Mix on low speed until flour is just combined. Transfer dough onto a sheet of plastic wrap. Form dough into a disc and wrap well. Place in fridge to chill; at least 1 hour. 

Preheat oven to 350°F (177°C). Place a 9 x 1-inch tart tin with a removable bottom onto a baking sheet.

Allow dough to come to room temperature; about 5 to 10 minutes.

Between two sheets of lightly floured parchment, roll dough into a round (at least 11 inches in size) to between ¼- to ⅛-inch thickness. 

Carefully lift the rolled dough and place into the tart tin. Gently press dough into place. With a rolling pin or the palm of your hand, scrape off the excess dough from the rim. Gently press the dough on the sides of the tart tin so that the dough rises slightly above the rim. This helps with any shrinkage that may occur during baking. With a fork, poke the tart shell all over.

Place baking sheet into the freezer to chill; 15 minutes.

Place a piece of parchment, larger than the tart tin, into the chilled tart shell. Fill with baking weights, dried beans, or uncooked rice.

Place baking sheet into the preheated oven. Bake the tart shell for 15 to 20 minutes, rotating halfway through. Carefully remove parchment paper and weights. Place shell back into the oven and continue baking until golden in colour; 8 to 10 minutes.

Remove from oven and place onto a wire cooling rack. Allow tart shell to cool completely in the tin before filling.

In a medium pot over medium heat, stir together the milk, 2 tablespoons (25 g) of the Redpath®  Organic Granulated Sugar, rose petals, and cardamon pods (crushed using a mortar and pestle; husks and any uncrushed seeds will be strained out) until it just starts to simmer and sugar is dissolved. Turn off heat and cover pot. Allow to infuse; 10 to 15 minutes.

In a medium bowl, whisk together remaining ¼ cup (50 grams) sugar, cornstarch, and salt until well combined. Add in the yolks and whisk until thoroughly blended.

Temper yolks by ladling a small amount of the hot milk into the eggs while continuously whisking. Repeat the process until the temperature of the eggs feels about the same as the temperature of the milk.

Pour and whisk in the remaining milk into the egg mixture. Strain the milk mixture back into the pot. Discard rose petals, cardamom husks, and any bits of cooked egg.

Place pot over medium heat, continuously stirring with a rubber spatula. Once mixture starts to thicken, switch to a whisk, and lower temperature to medium-low. Whisk continuously until mixture begins to bubble and thicken; cook for 2 minutes.

Remove from heat. Whisk in the vanilla extract until thoroughly combined into the pastry cream. Add butter. Fully incorporate butter into the pastry cream.

Transfer pastry cream into a clean bowl or shallow dish. Place a piece of plastic wrap directly over the surface of the cream. Ensure that the plastic wrap is in contact with the entire surface of the pastry cream as it will form a skin in the areas that it does not. Allow to chill in the fridge until cold; at least an hour.

Whisk chilled pastry cream before using, to ensure a smooth consistency.

Pastry cream can be kept covered in the fridge for up to 5 days.

Carefully remove tart shell from the tin and place onto desired serving plate.

Transfer the whisked, chilled pastry cream into the cooled tart shell. With an offset spatula, evenly spread and smooth pastry cream to the edges of the shell. 

Wash, dry, and thinly slice plums. If desired, dip one of the cut sides of the plums into the Redpath® Organic Granulated Sugar. Arrange the sliced plums, sugar side up (if using), onto the surface of the tart. Sprinkle tart with rose petals, if desired.