Decadent Fudge Sauce

1 12 ounce can evaporated milk
1 12 ounce bag semisweet chocolate chips -- (2 cups)
1/2 cup sugar
1 tablespoon butter or margarine
2 teaspoons orange-flavored liqueur -- if desired or 1 teaspoon orange extract

Heat milk, chocolate chips and sugar to boiling in 2-quart saucepan over medium heat, stirring constantly; remove from heat. Stir in butter and liqueur until sauce is smooth and creamy. Serve warm over ice cream. Store covered in refrigerator up to 4 weeks. About 3 cups sauce.

SUBSTITUTION: Love raspberries and chocolate? Substitute 2 tablespoons raspberry-flavored liqueur for the orange. For classic fudge sauce, omit the liqueur and add 1 teaspoon vanilla.

VARIATION: If you like, use the microwave to whip up a batch of Fudge Sauce Mix milk, chocolate chips and sugar in 8-cup microwavable measure. Microwave uncovered on High 6 to 8 minutes, stirring every 2 minutes, until thickened and smooth. Stir in butter and liqueur until sauce is smooth and creamy.