In a food processor, pulse together the flour, salt, and sugar. Add the chilled, cubed butter and pulse a few times until the butter pieces are about the size of peas. Stream in the cold water while pulsing until the dough just comes together.

Move the dough to a bowl or lightly floured surface and gently knead into a ball — be careful not to overwork it. Wrap in plastic wrap and flatten into a rectangle about 1/2" thick. Chill in the refrigerator for 2 hours.

While the dough chills, blend the strawberries, honey, and lemon until smooth. Strain the purée through a fine-mesh sieve into a saucepan to remove seeds.

Cook the strained strawberry purée over medium heat for 20–25 minutes, stirring occasionally, until reduced and thick.

Preheat the oven to 300˚F and line a sheet pan with parchment paper.

Divide the chilled dough in half. Roll each half into approximately a 14 x 14" square, keeping it thin (about 1/8").

Cut the rolled dough into roughly 3.5 x 4.75" rectangles, needing two per pop tart.

Spoon about 1 tablespoon of the cooled strawberry filling in the center of half the rectangles. Brush egg yolk around the border of each filled rectangle, dock the top rectangles, place over filled bottoms, and crimp the edges to seal.

Transfer to the prepared sheet pan and bake for 30–35 minutes, until golden.

Whisk together the powdered sugar and milk for a glaze, then spread on cooled pop tarts and add sprinkles if desired.