This recipe comes from Chef Achatz of Chicago's Alinea restaurant. is very high in butter, but it's worth all the work and all the calories. It combines aroma and flavour in a unique fashion: Bowls of steaming rosemary vapour accompany the luxurious main course. The piney fragrance of fresh rosemary adds another level to the taste experience. I bought cooked lobsters from a fish shop to help streamline the process.

1 cup distilled white vinegar

4 750-gram (1 ½-pound) live lobsters

½ cup canola oil

3 carrots, peeled, thinly sliced

1 onion, thinly sliced

1 fresh fennel bulb, thinly sliced

2 tomatoes, thinly sliced

4 fresh tarragon sprigs

8 cups fresh rosemary leaves stripped from branches

2 tablespoons butter

1 ½ cups (3 ¼ sticks) butter, room temperature

1 pound assorted fresh wild mushrooms (such as oyster, cremini, chanterelle and stemmed shiitake), cut into 1-inch pieces

4 large fresh thyme sprigs

3 garlic cloves, halved

Bring 8 quarts water and vinegar to boil in 10- to 12-quart pot. Add 2 lobsters head-first and cook until shells turn bright red and lobsters are just cooked through, about 11 minutes. Using tongs, remove lobsters from water. Repeat with remaining 2 lobsters. (Or purchase already cooked lobster). Twist claws and tails off lobsters.

Crack claws and remove meat. Using kitchen shears or heavy large knife, cut lobster tails lengthwise in half; remove tail meat. Cut meat into large bite-size pieces. Place in medium bowl; cover and refrigerate. Reserve claw and tail shells.

Rinse shells under cold water. Place in large bowl. Pour cold water over and soak 10 minutes. Drain and rinse well.

Heat ¼ cup oil in large pot over medium heat. Add lobster shells, carrots, onion, fennel, tomatoes and tarragon. Cook until vegetables begin to soften, stirring occasionally, about 15 minutes.

Add 4 quarts water and simmer 45 minutes, stirring occasionally. Strain lobster broth into large bowl, pressing on solids. Strain broth again through fine strainer into same pot.

Boil over medium-high heat until broth is reduced to 2 cups. (Can be made 1 day ahead.) Cool slightly; chill broth and lobster meat separately.)

Bring 1 quart water to boil in tea kettle. Place 1 cup rosemary in each of 8 large bowls; place on table.

Melt 2 tablespoons butter with ¼ cup oil in large skillet over medium-high heat. Add mushrooms, thyme and garlic and sauté until mushrooms are tender, about 6 minutes. Discard thyme and garlic. Add lobster meat and ½ cup butter to skillet and heat through, about 3 minutes.

Meanwhile, bring lobster broth to simmer in small saucepan. Pour hot lobster broth into blender; add 1 cup butter. Blend until butter is melted and mixture is frothy, about 30 seconds.

Divide lobster mixture among 8 shallow bowls. Pour butter sauce and foam over lobster mixture and serve. Pour 1 cup boiling water into each bowl of rosemary to create vapour. Wow.