Adapted from Cooking Classy
In a food processor pulse together flour, salt and granulated sugar. Add butter and pulse mixture until resembles coarse meal
Add the water and pulse several times, if it doesn't come together in clumps add a small amount more water.
Roll mixture into a ball wrap with plastic wrap and chill in the fridge for 1 hour.
Line baking sheets with parchment paper, roll dough out onto a floured surface to about 13 by 11 inch rectangle then trim edges for even cuts. Cut into desired size rectangles.
Arrange cut rectangle spaced evenly apart on prepared baking sheet then spread about 1 1/2 tablespoons of jam evenly down the center of each rectangle, leaving about a 3/4-inch rim on all sides.
Top each with another rectangle, then seal edges with a fork and poke the top center of each tart about 4 times with a toothpick.
Preheat oven to 375°F and Bake frozen tarts until golden, about 25 - 30 minutes.
While baking make the icing by whisking together all icing ingredients.
After they've cooled spread the icing on top of the pastries and top with sprinkle
Servings 4