Peel shrimp and devein, if desired. Soak shrimp in half-and-half 10 minutes. Drain shrimp, and dredge in flour. Fry shrimp in hot oil over medium-high heat 3 minutes on each side or until golden.
Whisk together egg yolk and lemon juice in a heavy saucepan. Add 1/4 cup butter, and stir over low heat until melted. Add garlic and remaining 1/4 cup butter. Cook, stirring constantly, until butter melts and sauce thickens; stir in parsley. Pour sauce over shrimp, and serve immediately.
Pour 2002 Brampton Unoaked Chardonnay. Wonderful pear flavors come through and stand up to this mildly citrusy dish.