Ginger Orange Chicken

4 chicken breasts
1/2 cup flour
salt and pepper to taste
2 T butter
1 T olive oil
1 T green onion, minced
1 cup fresh orange juice
1 T brown sugar
1/2 t peeled and grated fresh ginger
2 t Dijon mustard
1 orange

Remove excess fat from chicken breasts.  Rinse and pat dry with paper towels.  Place between 2 sheets of plastic wrap and flatten to an even thickness, using a rolling pin or meat mallet.  Put the flour on a plate.  Lightly salt and pepper each breast and then lightly coat with flour, shaking off any excess.
In a large saute pan over medium heat, melt the butter with the olive oil.  When hot, add the chicken and saute, turning once, until lightly browned and opaque throughout when pierced with a knife, about 5 minutes on each side.  Transfer to a plate and keep warm.
Pour off any excess fat from the pan and place the pan over medium-high heat.  Add the green onion, orange juice, brown sugar, ginger and Dijon mustard and mix well, scraping up any browned bits from the bottom.  Cook, stirring, until thickened and reduced, about 5 minutes.  Taste and adjust the seasonings.
Return the chicken to the pan and turn the breasts over several times to coat them well with the sauce.  Transfer to a warmed serving plate or individual plates and spoon the remaining sauce over the breasts.  Top with zest from the orange.  Serve immediately.