Prep the rhubarb. Pull the long fibres off the rhubarb from top to bottom with a paring knife. Frozen rhubarb works too.

Cook the compote. Cut the rhubarb into equal pieces and cook it in a skillet or small Dutch oven at 200°C. Add 30 g sugar, 100 ml water and 100 ml red juice (to keep the colour). Scrape out the vanilla pod and add the seeds and the pod, add the cinnamon stick, and let it simmer gently until it turns liquid.

Thicken. Remove the vanilla pod and cinnamon stick. Make a slurry of cornflour and cold water and use it to thicken the compote. It has to come to the boil for this to work.

Make the dough. Mix all the dough ingredients together and knead into a smooth dough. Wrap in foil and rest in the fridge for 30 minutes.

Line the skillet. Roll out the rested dough on a floured, smooth surface to an even thickness. Lightly butter a skillet, cut a piece of baking paper to cover the inside, and butter it again. Lay the dough all around the inside and pour the compote on top.

Make the crumble. Mix the sugar, butter and flour and work into loose pieces. Gently fold in the oats last, without squeezing the crumble together anymore.

Bake. Scatter the crumble over the top and place the tart on The Bastard at 210°C. Bake for about 20 to 25 minutes, then let cool.

Serve. Cut a wedge or spoon a generous portion onto a plate and add a scoop of vanilla ice cream.