Whisk together flour and salt in a medium bowl. Beat together butter and cream cheese until very light and fluffy. Gradually add flour mixture on low speed, mixing just until blended, scraping down bowl once or twice.
On a lightly floured surface, divide dough in half and pat each half of dough into a 12-inch round and wrap in plastic wrap. Chill in refrigerator 1 hour.
Meanwhile, heat strawberries, granulated sugar, lemon juice and 1/2 teaspoon cinnamon to a boil in a medium saucepan over medium-high heat, stirring occasionally. Reduce heat to medium and simmer until thickened slightly, about 15 – 18 minutes, stirring and mashing berries with a spatula or potato masher. Remove from heat and let cool completely. The mixture will thicken as it cools.
In a small bowl, combine icing sugar and remaining 1/4 teaspoon cinnamon and set aside.
Once filling is cooled and dough has chilled, preheat oven to 180°. Line 2 cookie sheets with parchment paper.
Remove 1 dough round from refrigerator. On a lightly floured surface, with a floured rolling pin, roll dough to a 12-inch circle about 1/4-inch thick. Spread half strawberry filling over dough in a thin layer.
Using a pizza cutter or sharp knife, cut dough round into 16 wedges. Sprinkle with half pistachios. Roll each cookie up starting with wide end of wedge and place on prepared cookie sheet. Repeat process with second round of dough, remaining pistachios, and the rest of the filling.
Brush cookies with egg wash and sprinkle with cinnamon sugar. Bake cookies about 30 minutes or until golden on bottom, rotating baking sheets halfway through baking. Allow rugelach to cool on wire rack.