8ouncesunsalted butter,cubed and cut into small pieces
1large egg
2tablespoonsmilk (whole or 2% preferably)
For the Filling
1/2cup+ 2 tablespoons blueberries (see notes)
3tablespoonslight brown sugar
1 1/2tablespoonscornstarch
1 1/2teaspoonsground cinnamon
1largeegg,lightly beaten
Instructions
Prepare the Dough: Place the flour, sugar and salt in the bowl of a food processor. (If you don’t have a food processor, you can do the following steps by hand in a bowl with a whisk and fork). Pulse the ingredients a few times to combine, then add the butter and pulse several more times until the ingredients look like coarse cornmeal with larger pieces of butter scattered around. Add the egg and milk to the stand mixer while the machine is running until the ingredients are just combined.
Divide the dough in half, wrap in plastic film, flatten, and chill for 30 minutes.
Prepare the Filling: In a small bowl, stir together the blueberries, brown sugar, cornstarch and cinnamon until evenly combined.
Preheat to 325 degrees F. Note: If you have parchment sheets, you can use one in the next step one to draw out your measurements with a ruler before rolling out the dough. Then roll the dough directly onto the parchment, staying within the lines. A pizza cutter is also very helpful if you have one.
Place one piece of dough on a floured surface and roll into a rectangle that can be trimmed to 9x12 inches. Transfer to a parchment-lined baking sheet. Follow the same steps with the second piece of dough so each is on its own baking sheet.
Use a ruler to divide each rectangle into thirds, both lengthwise and crosswise. You’ll wind up with nine 3x4-inch rectangles (this is when the pizza cutter is very helpful).
Brush the edges of one 3x4 rectangle with egg, then scoop 1 tablespoon of filling into the center. Top with a second rectangle, then use a fork to crimp the edges all the way around. Repeat this process until you have 9 tarts. Prick the top of each tart 3 times with either a fork or a paring knife so steam can escape.
Bake for 25-30 minutes, or until the tarts are a light golden brown. Allow them to cool on the pan before serving.
Store leftovers in an airtight container in the refrigerator for up to one week, or freeze for up to one month. Reheat in a toaster oven or in the microwave (don’t use a regular toaster).
Notes
I used frozen wild blueberries for this recipe. Wild blueberries are smaller, so I found that they fit better into the tarts. However, you can use regular blueberries, frozen or fresh. Do not thaw frozen berries before using.If you really don't want to make homemade dough, you can get away with using store-bought pie dough for this recipe.Crust and steps adapted from King Arthur Flour.