Trim fat from meat; cut meat into 4 portions. Place between pieces of plastic wrap. Pound to 1/4-inch thickness. In a shallow dish, combine buttermilk and egg. In another dish, mix the 1/2 cup flour with 1/2 teaspoon salt and 1/4 teaspoon pepper. Dip meat into egg; coat with flour mixture.
In a 12-inch skillet, heat 2 tablespoons hot oil over medium heat. Cook cutlets for about 8 minutes or until coating is golden and meat no longer is pink, turning once.
For gravy: In a saucepan, melt butter. Stir in the 3 tablespoons flour and the garlic. Add 1/4 teaspoon pepper. Combine milk and bouillon. Stir in milk mixture all at once. Cook and stir until bubbly. Cook for 1 minute more. Serve with gravy.