Place chicken in a resealable plastic bag with flour, salt, and pepper. Seal bag and shake to coat.
Remove chicken from bag, shaking off excess flour.
Heat oil in a large skillet over medium high heat. Brown chicken on each side for about 5 minutes, or until golden.
Remove from skillet and set aside.
In same skillet combine sherry, broth, garlic and a squeeze of lemon and bring to a boil. Return chicken to skillet, reduce heat to low and simmer for 15 to 20 minutes, or until chicken is cooked through and no longer pink inside.
In the meantime, saute carrots and zucchini in a separate medium skillet until they are tender.
Add to simmering chicken and sauce and heat through before serving.