Preheat oven to 350℉ and line a baking sheet with parchment paper.
In a medium bowl, add the flour, baking powder, and salt. Stir to combine.
Add the full-fat Greek yogurt, brown sugar, and vanilla to the bowl and mix until a shaggy dough starts to form.
Turn dough out onto a lightly floured surface. Knead gently to form a smooth ball of dough. If the dough feels sticky, sprinkle with a little extra flour as needed.
Roll the dough with a lightly floured rolling pin into a rectangle shape. Then slice the dough lengthwise down the middle, and then again, about 5 times, in the opposite direction to form small rectangles (about 10 in total).
Place 5 of the rectangles onto the lined backing sheet. Spoon out just under a tablespoon of the strawberry chia jam into the middle of each rectangle. Then place the other rectangle pieces on top. Seal each one by gently pressing with a fork around the edges. Brush a little melted coconut oil on top.
Bake the pop tarts for 20-24 minutes, until golden brown on top. Allow to cool before adding optional glaze.
These pop tarts are delicious without the frosting, but if you'd like to add a frosting, mix together the powdered sugar, milk, and vanilla and whisk together until a thick frosting forms. Once the pop tarts have cooled, add the frosting. Optional to add a few sprinkles on top!