Preheat your oven to 375°F (190°C) and lightly grease your pie dish with a little coconut oil.

Wash the rhubarb and strawberries thoroughly. Slice the rhubarb into half-inch pieces and hull the strawberries, cutting larger ones into halves or quarters.

In your large mixing bowl, combine the fruit, coconut sugar, lemon zest, vanilla, and cornstarch. Toss gently and let it sit for ten minutes to release the natural juices.

Press your favorite plant-based pie crust into the dish, using a store-bought vegan crust or a quick homemade version using flour and chilled coconut oil.

In the medium bowl, combine the oats, flour, sugar, and salt. Add the chilled vegan butter or solid coconut oil.

Use your pastry cutter or fingertips to work the fat into the dry ingredients until the mixture resembles coarse crumbs.

Pour the fruit mixture into the prepared crust, ensuring an even distribution of the rhubarb and strawberries.

Sprinkle the crumb mixture generously over the fruit until you cover the entire surface of the pie.

Place the dish on a baking sheet and slide it into the oven. Bake for 45 to 55 minutes until the filling bubbles and the topping turns golden.

Remove the pie from the oven and let it cool completely on a wire rack for at least two hours before slicing.