In a shallow bowl, mix flour with salt and pepper.
In another bowl, whisk eggs, sugar, and Parmesan until fully blended.
Heat olive oil in a large skillet over medium heat until shimmering.
Dredge chicken in flour, then dip into egg mixture.
Pan-fry chicken until golden and cooked through, about 6 minutes per side. Remove and set aside.
In the same skillet over medium-low heat, melt butter and sauté garlic for 30 seconds.
Add sherry, lemon juice, and chicken base. Simmer and stir, scraping browned bits, until sauce slightly thickens (about 5 minutes).
Return chicken to skillet and gently simmer in sauce for 15 minutes.
Serve chicken topped generously with sauce.