To make the topping:

Add brown sugar, almonds, whole wheat flour, whole wheat flour, oats, cinnamon, anise seed, five-spice powder, salt and butter in the bowl of a stand mixer fitted with the paddle attachment. Mix on low speed until well combined and it has started to form a dough, about 5 minutes. Transfer to a ziplock bag and place in the refrigerator until ready to use.

To make the filling:

Preheat the oven to 400℉ (200℃) and adjust the oven rack to the middle position. Grease an 11x7 inch baking dish or a 9 inch round deep-dish pan with vegan butter or oil and set aside.

Combine about 6 cups (700 grams) of rhubarb with the sugar, taipoca flour, elderflower cordial or liqueur or water, ginger, vanilla pasta and salt. Toss well and transfer to the baking dish. Cover with foil and place in the oven for 30 minutes until the rhubarb starts to wilt and release juices.

While the rhubarb is in the oven, combine the remaining rhubarb with the strawberries in a bowl (about 2 cups/265 grams).

Take the rhubarb out of the oven after 30 minutes and sprinkle over the baking and stir carefully to combine it into the rhubarb mixture. It should start to fizz. Pour over the remaining rhubarb and strawberries and top with the prepared streusel. Pat down carefully and make sure there is an even layer on top.

Place the rhubarb crumble back into the oven, uncovered, and cook for another 30-35 minutes until the fruit bubbles underneath and the streusel topping is nice and brown.

Let the crumble cool on a rack for about 30 minutes before serving. The crisp will thicken as it cools down. Serve with a dollop of vegan vanilla ice cream or vegan whipped cream!