Preheat oven to 400°
In a large bowl, combine butter and sugar. Mix until fluffy and well combined.
Add in the eggs, one at a time.
Next, add vanilla and mix until combined.
In a small bowl, whisk flour, baking powder, and salt until combined.
Slowly add dry ingredients to wet ingredients and mix until the dough is formed.
Transfer to a floured surface and knead for 8-10 minutes.
Cover dough with a clean cloth and let rest for 30 minutes.
Divide the dough in half and roll each half out into a ¼ in. thick rectangle.
Cut each rectangle into 4x3 inch rectangles.
Add fresh fruit, sugar, and lemon juice into a small saucepan.
In a small bowl, mix together water and corn starch. Set aside.
Cook over low medium heat, continuously stirring.
Once fruit mixture starts boiling, add in corn starch and water mixture.
Continue cooking and stirring for 8-10 minutes.
Remove from heat and set aside to cool.
Save 1 tablespoon of filling for the frosting.
In a small bowl, whisk the powdered sugar, fruit filling, and milk until icing is smooth.
Place frosting in refrigerator until pop tarts have cooled completely.
Take the 4x3 rectangles and add a spoonful of filling into the center.
Brush the edges of the dough with egg white and place another 4x3 rectangle of dough over the top.
Using a fork, seal the edges of the pop tarts together.
Poke the top 3-4 times with a fork and place on baking sheet.
Brush top of each pop tart with the remaining egg white.
Bake for 20-24 minutes or until golden brown.
Once cooled, top with frosting and candied sprinkles, if desired.
Dough recipe adapted from Blue Jean Chef's Air Fryer Genius cookbook, pg 260