Look for whole spikelets with half-open flowers.  Lavender is usually sold in plant form along with other herbs. Check with the producer to be sure you’re getting a culinary variety and not the “officinale” variety.

Fresh
Place the stems in a glass of water and refrigerate.

Dried
Lavender keeps its powerful aroma for a long time. Simply store it in a bag and keep it away from light and heat. 

When it comes to cooking, lavender needs to be used with great care. A single flower may be enough to flavor an entire dish. It is best to add it in small amounts, tasting as you go, since too much will impart a bitter taste more suited to soap-making than cooking!

Use lavender flowers in a milk infusion, sugar syrup, liqueur or vinegar.

They can also be used in pastry making and, like thyme, in Provençal-style meat stews and braises.

When the flowers are dry, throw them onto the barbecue coals to flavor grilled foods.

You can…
> Make them into jelly with apple juice     

> Add 1 tsp. powdered lavender flowers to a cheesecake. When you make the crust, replace one-third of the flour with ground almonds. 

> Add a pleasant flavor to yogurts, floating island, sorbet, and chocolate creams. 

In Grasse, the French perfume capital, lavender, rosemary and wild thyme are pulverized and rubbed onto lamb shoulder before it is roasted or cooked on a spit.

Lavender ice cream
Add 1 tsp. lavender flowers to 250 ml cream, 250 ml milk, 200 g sugar and 8 egg yolks.

Crystallized lavender for cake decorations
Beat an egg white with 125 ml sugar; brush onto the flowers and dry on a rack for 24 hours.

Lavender sugar
Pour 1 kg powdered sugar and 1 tbsp. lavender flowers into a jar. Close and shake to mix well. Try it on fruit salads or ice cream, or to flavor cakes, cookies, candies and summer drinks.