Use fresh or frozen rhubarb, and slice into 1' chunks.

Slice the strawberries.

Combine the rhubarb, strawberries, sugar, and cornstarch into a pot and turn to medium-low until the mixture boils. 

Turn the mixture to low and stir occasionally so the bottom doesn't burn until thickened ~ 15 minutes. 

For the pie crust mix the flour, salt, and sugar into a large bowl. 

Shred the butter using a cheese grater into the flour mixture and toss with your fingers.

Add the cold water to the flour mixture.

Pour half of the flour/water mixture onto a floured wooden cutting board and squish it together with your hands until the mixture holds together.  

Roll the pie crust out onto the cutting board and place into a buttered deep dish pie crust. 

Pour the rhubarb and strawberry mixture into the bottom pie crust. 

Roll out the other half of the pie crust mixture as above and place over the pie mixture.

Use a butter knife to cut off the extra pie crust, and fold or crimp the edges of the pie crust pressing the crust against the corner of the pie plate. Slice some slits into the top of the pie crust for vents.