Add sugars & starch to a non-reactive glass dish.

Add half of the rhubarb to the sugar mixture.

Toss the fruit in the sugar and roast in the oven.

Remove the roasted rhubarb from the oven.

Add baking soda and stir to combine.

Add the remaining rhubarb and vanilla to the mixture.

Roll the pie crust into a circle to fit the pie plate.

Line the pie plate with the bottom crust.

Pour chilled rhubarb mixture into the pie crust.

Cut the 2nd piece of rolled dough into strips.

Arrange the strips of pie dough into a lattice pattern.

Cut off the excess dough and crimp the edges.

Brush the top crust with milk and coarse sugar, then put in the fridge to chill.

Bake the chilled pie for 30 minutes at 400ºF.

Rhubarb Pie with All-Butter Lattice Crust