Mix together flour, salt, and pepper in a shallow bowl.
Whisk beaten eggs, sugar, and Parmesan cheese in another bowl until the mixture is thoroughly blended and the sugar has dissolved.
Heat olive oil in a large skillet over medium heat until the oil shimmers.
Dip chicken breasts into the flour mixture, then into the egg mixture, and gently lay them into the skillet.
Pan-fry chicken breasts until golden brown and no longer pink in the middle, about 6 minutes on each side.
Remove from the skillet and set aside.
In the same skillet over medium-low heat, melt butter, and stir in garlic.
Add sherry, lemon juice, and chicken base.
Bring the sauce to a simmer, and stir until smooth and slightly thickened, about 5 minutes.
Return chicken breasts to the sauce, and gently simmer for about 15 minutes.
To serve, place a chicken breast on a plate, and top with sauce.
