Abby's Famous Penuche Fudge

1 1/2 cups granulated sugar
1 cup packed brown sugar
1/3 cup light cream
1/3 cup milk
2 tablespoons butter or margarine
1 teaspoon vanilla extract
1/2 cup walnut pieces

Butter a 9-inch square baking dish. Butter the sides of a heavy 2-quart saucepan.

Combine sugars, cream, milk and butter in saucepan. Cook over medium heat, stirring constantly, until sugars dissolve and mixture comes to a boil. Cook to soft-ball stage (238 degrees F on candy thermometer), stirring only if necessary. Immediately remove from heat and cool to lukewarm (110 degrees F). DO NOT STIR.

Add vanilla extract and beat vigorously until mixture is very thick and starts to lose its gloss. Quickly stir in walnuts and spread into prepared baking dish. Score while warm, and cut when firm.

Makes 3 dozen 1 1/2-inch squares.