In a small saucepan, set over medium heat, stir together the orange juice, 125 g of the caster sugar, and 125 ml water. Gently bring to a boil, then reduce the heat a little, and simmer for 5 minutes. Set aside to cool completely.

Preheat the oven to 180°C (356°F). Grease and line the bottom of a 9" (24 cm) cake tin with parchment paper.

Crack open the cardamom pods and crush the seeds with a mortar and pestle***. Melt the butter in a frying pan (or skillet - if baking in one) over medium low heat. Sprinkle in 75 g of caster sugar and heat for 2-3 minutes. Sprinkle over the crushed cardamom seeds, stir, and take off the heat.

Place the butter mixture in the bottom of your cake tin (or leave in the skillet) and pile on the rhubarb.

In a large mixing bowl, whisk together the yogurt, oil, eggs, and orange zest. In another bowl, whisk together the semolina, flour, baking powder, ground almond, remaining 50 g sugar, and a pinch of salt.

Fold the dry mixture into the wet, until completely combined. Spoon mixture into the cake tin, starting around the edges to keep the rhubarb in the centre. Smooth over the top.

Bake in the oven for 40 minutes, or until a toothpick comes out clean.

Right after you take the cake out of the oven, pierce all over with a toothpick, and pour over the cooled syrup (do not remove from pan).

Leave the cake in the pan for 5 minutes, then invert onto a plate. Sprinkle over the pistachios (if using) and allow to sit for at least 20 minutes to fully absorb the syrup.

Serve with some additional greek yogurt (sweetened if desired).