1) Rinse the (thawed) shrimp under cold running tap water and let them drain on some paper towels.
2) Trim the fennel bulb. Slice it up lengthwise and chop the slices roughly.
3) Pour a little olive oil in a wok and place it over medium heat until hot. Then add the chopped fennel and stir fry it for about 4 minutes. Season with a little pepper and salt.
4) Add the shrimp when the fennel starts to brown lightly. Stir fry for another 3 minutes until the prawns are pink. Then turn off the heat. Check the seasoning of the sauteed shrimp and add extra pepper or salt to taste.
5) Transfer the sauteed shrimp and fennel onto plates. Drizzle with the remaining oil. Serve immediately.