In the bowl of a food processor fitted with a dough blade, combine flour, sugar, salt, and baking powder.
Pulse until combined.
Add butter, a few Tablespoons at a time.
Pulse until broken up and coated with flour mixture.
Add egg and cream.
Pulse until mixture comes together.
Remove dough from food processor.
Divide into 2 even portions.
Shape each into a rectangle.
Wrap each half in plastic wrap.
Refrigerate for 1 hour.
While dough is chilling, heat oven to 350℉.
Line sheet pan with parchment paper. Set aside.
Remove dough from refrigerator, one piece at a time.
Place dough on a piece of parchment paper.
Roll into a rectangle that is ⅙ inch thick.
Cut out 8 rectangles using a 4½ inch x 3 inch cutter, re-rolling as necessary to get the full number.
Place rectangles on prepared sheet pan.
Top each with 1 Tablespoon strawberry jam. Set aside.
Repeat rolling and cutting process with 2nd piece of dough.
Place a rectangle of dough over each of the filled pieces.
Gently press to remove air.
Press edges together gently with finger.
Use a fork to press around the edges to ensure each pastry is sealed.
Prick the tops of each pastry with tines of fork.
Bake for 30 minutes, until lightly browned around edges.