Step 1

Combine butter, flour, and salt. Using a pastry blender cut in the butter until very crumbly. Add chilled water a few tablespoons at a time mixing with a fork until the dough pulls together.  Form into a disk, wrap in plastic, and chill for at least 2 hours.

Step 2

Whisk together flour, sugar, and brown sugar.  Cut in butter using a pastry blender until crumbly.  Set aside.

Step 3

Mix together rhubarb, strawberries, sugar, brown sugar, cornstarch, and vanilla extract.

Step 4

Gently roll the piecrust out to a 12 inch circle on a lightly floured surface.  Fold the piecrust or roll it around your rolling pin to move it to the pie plate.  Gently tuck the crust into the pie pan, trim the edge about an an inch over the side, tuck the excess dough in along the edge and flute it.

Step 5

Spoon the fruit mixture into the pie crust and sprinkle with the streusel crumb topping.  Put on a rimmed baking sheet and bake in a preheated 375 degree oven for 50-55 minutes.  If needed cover with a loose piece of aluminum foil to keep from overbrowning.

Step 6

Cool completely before slicing.