Its florets should be pale green and form a crown.

Simply rinse under cool running water.

Trim the heavy stem base and leaves.

It cooks quickly, so keep an eye on it to preserve the shape of the florets and its nutritional value.

Delicious and unique, it takes well to steaming, microwaving and wok stir-frying. Because its florets are small and even, it needs only a short (5 à 7 minute) cooking time. Once cooked, serve it right away.

Steaming
Set it stem end down in a heavy pot in 3/4" boiling water. Cover tightly and cook over moderate heat until tender throughout, 7 - 8 minutes.
 

For a taste of the Reunion islands, mix the juice of a combawa, a variety of lime, into a Romanesco purée.

Steamed Whole Romanesco with Pine Nuts and Peppercorns
Stem whole head Romanesco. Meanwhile, in a small skillet, heat 3-4 tbsp. butter over low heat until pale golden. Add 2-3 tbsp. pine nuts and 1 tsp. green peppercorns and toss to coat.
Place the Romanesco in a dish; pour the peppercorn and pine nut butter over top and serve hot.