Melt butter in a large Dutch oven over medium-high heat. Add mushrooms; sauté 3 to 4 minutes or until mushrooms begin to brown. Add shallot; cook 4 minutes or until translucent. Add sherry, stirring to loosen particles from bottom of pan.
Add carrots, parsnips, potatoes, and peas to pan; stir in fish broth.
Bring mixture to a boil. Stir in cream, and return mixture to a boil. Reduce heat to low, and simmer 12 minutes or until vegetables are tender. Stir in lobster, salt, and pepper. Add parsley and chives; serve immediately.
*Note: Go to coastalliving.com for a great lobster stock recipe.