With paper towels, pat liver dry.
Cut into strips 1/8 inch wide (see Note).
On sheet of waxed paper, combine flour, salt, and pepper.
Roll liver in mixture, coating well.
In large skillet, heat butter and 2 tablespoons oil.
Saute' liver strips, turning frequently, until lightly browned on all sides—about 5 minutes.
Remove, and set aside.
Add remaining oil to skillet.
Saute onion slices, stirring frequently, until golden—about 10 min- utes.
Add sage.
Cook, covered, over low heat 5 minutes.
Combine liver with onion, tossing lightly.
Cook, covered, over low heat 5 minutes.
Remove liver and onion to serving dish.
To drippings in skillet, add white wine and lemon juice; bring to boiling, stirring.
Pour over liver and onion.
Sprinkle with chopped parsley.
Nice served with slices of hot polenta.
Makes 6 to 8 servings.
Note: To make liver easier to slice thinly, place in
freezer long enough to chill thoroughly.