Cherry Vanilla Shortbread Tart

It has been such a long, weird spring (cool temperatures, coronavirus isolation) so when I saw cherries for sale I had to remind myself that normally by now it feels like summer. My family's favorite cherry thing, other than eating them straight from the bag, is this cherry tart recipe. And, because the kids are schooling at home and starved for entertainment, I asked them to help me make it. In the past I used our 11" tart tin with the recipe linked there even though the recipe calls for a 9" one. But it's Memorial Day weekend and we want to share this safely with friends who are isolating, so I decided to make two 9" tarts. I could have just doubled the original recipe, but I decided to turn it into a math lesson instead. If one tart recipe fills an 11" tin, how much more does Olivia need to make two 9" tins? And because we plan to do this again, here is the recipe scaled for two 9" tarts and tweaked a bit. This is a bit rich, so go easy on portion sizes. Maybe next time I'll add a cream cheese layer.

Update 5/29/21 (apparently this is a Memorial Day thing): I had the pleasure of picking tart cherries from my friend Carmen's tree and they balanced out the richness of the shortbread. They were also less juicy, so the shortbread still looked good and not soggy the next day, and they didn't stain my fingers the way sweet cherries do.

Cherry Vanilla Shortbread Tarts

Ingredients
1 cup + 5 Tbs butter, room temperature
⅔ cup sugar
⅓ cup light brown sugar, packed
1 Tbs + 1 tsp vanilla bean paste
3 cups all-purpose flour
½ teaspoon salt
1⅓ cup of plum or cherry jam, warmed in microwave
2 cups fresh cherries, pitted 

For the vanilla icing:
⅔ cup powdered sugar
1½ tsp vanilla bean paste
1½ Tbsp melted butter
1½-2 Tbsp milk

1. Preheat the oven to 350F. 
2. Grease two 9-inch removable-bottom tart tins and place them on baking sheets. 
3. Using a mixer fitted with the paddle attachment, beat the butter, sugar, vanilla and brown sugar vigorously until pale and fluffy, about 3 minutes. It’s an important step to beat the butter and sugar well together when making shortbread as this ensures the shortbread is light, crisp and will hold together. 
4. In a separate bowl, sift the flour and salt. Add it to the butter mixture and mix until blended (forming large clumps). 
5. Turn onto a floured surface and using floured hands, press two-thirds of the mixture evenly into the prepared tins (including up the sides). Our dough weighed about 2lbs total, so 10oz went in the bottom of each tin and we crumbled the remainder on top.
6. Spread the jam evenly over the dough and then scatter with the cherries. Crumble the remaining dough over the filling. Bake the tarts for 40-45 minutes, until lightly browned. Leave to cool completely in the tins. 
7. For the vanilla icing: In a small bowl whisk together the powdered sugar, vanilla, butter and 1½ tablespoons of the milk. If it looks too thick, you can add a bit more milk. Drizzle the cooled tarts with the icing, remove sides from the pan, and serve on the base.