Preheat oven to 400°F. Line a cookie sheet with parchment paper
In a non-stick pan over medium heat, melt butter. While the butter melts, whisk 4 eggs together with the cream.
Add eggs to the pan and scramble for 3-4 minutes. Season with salt and pepper after they are soft scrambled. You don't want to overcook the eggs since they will also be baking inside of the pinwheels in the oven. Remove to a bowl.
Lay puff pastry out on the prepared cookie sheet with the creases on top facing you. Smooth out into an even rectangle with a rolling pin.
Place the hashbrown patties in the center of the puff pastry, smashing them to create an even layer. Leave a 1/2 inch border around the edges of the pastry dough. Put eggs on top, then cheese, bacon, and green onion leaving the 1/2 inch border in tact all the way around the pastry.
Whisk the last egg with 1 tbsp water. Brush this egg wash over the longest edge of the pastry dough that is farthest away from you.
Tightly roll up the dough like a jelly roll, working the dough closest to you inward. Make sure the dough is tightly rolled or the pinwheels will fall apart when you cut them.
Press the edge with the egg wash down against the pastry roll to seal the pinwheels. You can add more egg wash to the seam as needed to ensure it stays together.
Freeze for 15 minutes.
Take out of the freezer and with a sharp knife, slice the dough into 12 equal sized pinwheels. Place 2 inches apart from one another on the parchment paper.
Lightly brush the sides and tops of each pinwheel with egg wash using a basting brush.
Bake 25-30 minutes or until the dough is fully cooked and golden brown.