A chef friend once came to my house for lunch, bearing a gift he'd bought from the flower market in Mong Kok. But instead of being destined for a vase, the long, green stalks with tiny, bright yellow flowers at the tips were headed for the cooking pot. The chef had recognised the seemingly decorative flowers as the fennel plant, from which pollen could be harvested. The pollen is often sold as a dried spice in upmarket stores. There's a reason it's so expensive: it takes a lot of fennel flowers to get a small amount of pollen. You can harvest it yourself by holding the flowers upside down and brushing or shaking them over a dish, which will catch the golden dust as it falls. Fennel pollen is sweet, pungent and intense - and a little goes a long way. It pairs deliciously with meat and fish. In Tuscany, northern Italy, the pollen is one of the essential ingredients used for porchetta - delicious roasted pork stuffed and seasoned with copious amounts of salt, garlic, spices and herbs. For an easy fish dish, mix fennel pollen with salt. Cut deep slashes into both sides of the fish, cutting all the way to the bone. Sprinkle the fish inside and out with the salt-fennel mixture, then stuff the cavity with sliced lemon and stalks of fresh herbs (such as thyme, oregano and fennel fronds). Then mix a large quantity of rock salt with just enough egg white to moisten it and firmly pack the salt around the fish, encasing it entirely. Bake the fish in a hot oven. When cooked, carefully remove the rock-salt crust. Drizzle with extra-virgin olive oil and serve with lemon wedges.