Put the butter, sugar, flour, egg yolk and salt in a food processor and pulse for 30 to 60 seconds or until the mixture has a grainy consistency, or what I like to call the "Parmesan cheese" stage. Add half of the water and pulse the food processor 2 to 3 times. The dough should start to come together, add the remaining water if needed. Check the consistency of the dough by clenching a small handful in your fist. If the dough stays together it is the proper consistency. If not, pulse the dough with a little more water. When the dough has reached the proper consistency, dump it out on a clean work surface. Using the heel of your hand, schmear the dough straight forward and roll it back with your fingertips. Repeat this process 1 to 2 more times, dust with flour if needed. Form the dough into a disk, wrap in plastic wrap and refrigerate for at least 30 minutes.
On a lightly floured work surface, roll the dough out to 1/8 to 1/4-inch in thickness. Lay the dough in the tart pan. Push the dough into the sides of the tart pan by rolling a small scrap of dough into a ball and pushing it into the dough. Roll over the top edge of the tart pan with the rolling pin to cut the extra dough from the pan and create a crisp edge. Cover the dough with aluminum foil and gently poke the foil into the side edges to fit the pan. This will help to keep the sides of the tart tall and straight as it cooks. Fill the tart shell with the dried beans and place in the preheated oven. Bake for 10 to 12 minutes, remove the foil and beans and bake for 2 to 3 minutes more. Remove the tart shell from the oven and cool. The dough should be golden and crisp.
For the curd:
Preheat the oven to 300 degrees F.
In a bowl, combine the lemon juice, zest, sugar, eggs and salt and whisk to a homogeneous consistency. Place in saucepan and bring to a medium heat. Cook, whisking, constantly until the mixture has thickened, about 12 to 15 minutes. Remove from heat and whisk in the butter, 2 pats at a time until it's incorporated and has a silky consistency.
Pour the lemon curd into the prepared tart shell and bake in the preheated oven until the lemon curd has set, about 15 minutes. Let cool completely before cutting.
To garnish: In a small bowl, mix together blueberries, sugar and lemon juice. Serve alongside tart slices.