Whereas your berries and rhubarb are stress-free in a sugar and starch soak, which is able to thicken the filling on your straightforward pie, you possibly can work on the crumbly topping. So, in a separate bowl, you merely mix your entire different substances — the brown sugar, flour, old school oats, pecan items, and chilled, sliced butter.
Combine all the pieces along with a pastry blender. Shelbert explains which you could additionally combine the topping by pulsing it in a meals processor, or make issues even simpler, by utilizing your fingers. Your objective is for a rough meal to return collectively.
Okay, you might be able to assemble this delish dessert!