In a large bowl, add 30 ounces pure pumpkin puree, 1 ¾ cups packed light brown sugar, 1 ½ cups heavy cream, 1 cup half and half, 4 large eggs, 2 Tablespoons cornstarch, 1 Tablespoon vanilla extract , 1 Tablespoon pumpkin pie spice and 1 ½ teaspoons salt.
Whisk together until smooth and well combined, set aside.
On a clean work surface, unroll and place two of the 4 refrigerator pie crusts on top of each other.
Roll out into a rough 18x12 inch rectangle.
Mold the crust into a 10x15x1 jelly roll pan, and let the excess crust overlap the sides.
Fill with the pumpkin filling but do not overfill, there may be a little filling left over, but that’s okay.
Roll out the remaining 2 pie crusts like the first two. Carefully lay this one on top of the filling. Tuck the top crust under the bottom and crimp the edges.
Cut slits in the top crust so air can escape.
Bake for 30-35 minutes, tent with foil halfway through if it looks like it’s browning too much. It is done when the crust is golden brown, and a toothpick inserted into the pie comes out mostly clean, if it is a little moist, that’s okay, but any wet filling means it needs to bake longer.
Let it cool on the wire rack for 1 hour.
While the pie is baking, make the glaze. Place 6 Tablespoons half and half and 1 Tablespoon salted butter into a small saucepan over medium-low heat, stirring occasionally. Bring to a simmer. As soon as you see any bubbles, take it off the heat.
Allow the mixture to come to room temperature, about 45 minutes to an hour. Whisk in 1 ¼ cups powdered sugar a little at a time until fully combined then stir in 1 teaspoon vanilla extract.
After the pie has cooled for 1 hour, glaze it all over using a pastry brush. Wait 30 minutes, and glaze again. Wait another 30 minutes and glaze one final time.
Place the pie in the refrigerator for at least 6 hours or overnight to set up.
Slice and serve.
Notes
Make sure you only use a 10x15x1-inch pan for this recipe.
The glaze is optional but highly recommended.
This needs to set for at least 6 hours.
Make sure that you don't forget to cut slits in the top so the air can escape.