Preheat your oven to 350F. In a medium-sized bowl, whisk together flour, baking powder, and salt. Set aside.

In a standing mixer (or in a large bowl using an electric mixer) cream together the butter and sugar. Once creamed, add in the flax, vanilla, and nut milk and beat until well combined.

Add the bowl of sifted dry ingredients to the standing mixer and mix until just combined.

Line an 8*8 baking dish with parchment paper and press the dough into the tray so that it is even and flat. Add the dish to the oven and bake for 20 minutes.

While the shortbread is cooking, make sure rhubarb curd. Begin by chopping the rhubarb and adding it to a small saucepan along with the sugar and water needed for the curd. Bring to a boil, then simmer over low heat about 5-8 minutes until the rhubarb is soft and pierceable. Make sure to stir the rhubarb constantly while cooking.

Add the cooked rhubarb to a blender along with the coconut cream and blend until smooth. Transfer the smooth rhubarb puree back to the saucepan and whisk in the arrowroot powder.

Turn on the heat and cook the rhubarb until it thickens. This will only take about 3-5 minutes. Once thick, set aside and let cool to room temperature.

Remove the shortbread from the oven and top with the vegan rhubarb curd. Add bake to the oven and bake for 15 minutes.

Once cooked, remove from the oven and let the rhubarb bars cool completely to room temperature. Cover and place in the fridge for at least 1-2 hours to set. Once you are ready to eat, remove and top with powdered sugar right before serving. Enjoy!