Lavender makes fragrant and tasty breads, drinks, and desserts like cookies, cakes, or custards. It goes particularly well with chocolate or green veggies. I like lavender mixed with melted butter then used as a dip for steamed artichokes and sprinkled on roasted asparagus or sauteed peas.
According to What's Cooking America: Flowers and leaves can be used fresh, and both buds and stems can be used dried. Lavender is a member of the mint family and is close to rosemary, sage, and thyme. It is best used with fennel, oregano, rosemary, thyme, sage, and savory.
English lavender has the sweetest fragrance of all the lavenders and is the most commonly used in cooking. [...] Lavender has a sweet, floral flavor, with lemon and citrus notes. The potency of the lavender flowers increases with drying. In cooking, use 1/3 the quantity of dried flowers to fresh.
Note: Adding too much lavender to your recipe can be like eating perfume and will make your dish bitter. [...] A little goes a long way.