Preheat oven to 400
Thaw pie 10 min at room temperature. Prick bottom and sides with fork. Add pie weights (or uncooked beans)
Bake pie shell on baking sheet in senter rack for 12-15 minutes
Remove from oven and remove pie weights
Bake 10 minutes more (this helps crisp up the bottom of the crust which helps it hold together under the custard)
Let cool before filling.
In a bowl, toss rhubarb with 1/4 cup sugar.
In a separate bowl, whisk together flour, remaining sugar, eggs, butter and heavy cream until smooth & combined.
Pour filling into cooled pie crust.
Scatter rhubarb across entire pie. Feel free to push it down into the pie a little.
Sprinkle a few tablespoons of sugar over the top of the pie.
Bake at 400 for 50 minutes. Pie will be slightly puffed, golden brown and a little wobbly in the center. Be sure to cover crust if it starts to brown too much.
Transfer to a wire rack and cool for 1 hour.
Refrigerate until ready to serve.