In a 10- to 12-inch frying pan over medium-high heat, stir garlic in olive oil just until it begins to turn gold, 2 to 3 minutes.
Add shrimp and stir until almost completely pink, about 2 minutes.
Add sherry, parsley, and hot chili flakes and stir often until shrimp are barely opaque but still moist-looking in center of thickest part (cut to test), about 1 minute.