Pound chicken breasts with meat pounder to a uniform thickness. Dredge lightly in flour, shaking off excess.
In a large saute pan over medium-high heat, melt the butter and oil until it sizzles. Add the chicken breasts and saute, turning once or twice until cooked through and juices run clear. Remove chicken and set aside. Whisk in flour and cook for 1 minute until the mixture boils. Add lemon juice to the chicken stock and whisk into saute pan. Reduce heat to a simmer. Return chicken to pan to heat through, thickening sauce to desired consistency. Season to taste with salt and black pepper.
6. Serve the chicken on a bed of Basmati rice, and spoon the sauce over the chicken. Garnish with chopped parsley and lemon slices.