Crab with rhubarb, yoghurt, fennel and chilli | Gill Meller

Name: Crab with rhubarb, yoghurt, fennel and chilli | Gill Meller
Cuisine: European
Ingredients: 3 slim sticks forced rhubarb, cut into 5cm pieces; Finely chopped zest and juice 1 lemon; 2 tbsp caster sugar; 1 red chilli, deseeded and finely sliced; 1 tbsp fennel seeds, toasted and gently; crushed in a mortar and pestle; 4 tbsp extra-virgin olive oil; 350g thick Greek yogurt; 1⁄2 small bunch fresh parsley, leaves; picked and finely chopped; 200g white crabmeat; 50g brown crabmeat; A few fennel fronds, if available (you could use dill sprigs if you like); 4 slices sourdough