Dust shrimp with flour. Heat oil over medium high heat. Add shrimp and saute for 2 to 3 minutes, until half done. Add shallots. Saute one more minute until the shallots are tender. To pan, add garlic, parsley, stock, and lemon juice. Cook so that flavors combine and juices reduce down. Slowly add butter chunks while stirring, allowing butter to melt and blend with the sauce. Serve immediately.
Serves 6 for appetizers.