This recipe came from Fairfield Grocery employee Jane and her husband's good friend, Dr. Anne Peters of Edinburgh, Scotland. It uses white rice flour, which gives the shortbread a crispy texture. You can substitute all-purpose flour for the rice flour.
1 1/2 cups butter, softened and divided
2 cups all-purpose flour
3/4 cup white rice flour*
1/2 cup granulated sugar
Cooking spray for baking
1 (14-ounce) can sweetened condensed milk
1/4 cup light corn syrup
1 cup firmly packed light brown sugar
1 1/2 cups semisweet chocolate morsels
How to Make It
Pulse 1 cup butter, flours, and granulated sugar in a food processor 10 to 15 times or until crumbly. Press mixture evenly into a 15- x 10-inch jelly-roll pan coated with cooking spray for baking.
Bake at 350° for 18 to 20 minutes or until light golden brown.
Stir together remaining 1/2 cup butter, condensed milk, and corn syrup in a 2-quart heavy saucepan over low heat 4 minutes or until butter is melted and mixture is blended. Add brown sugar, and cook, stirring constantly, 25 to 30 minutes or until caramel colored and thickened. Pour evenly over baked cookie in pan, and spread into an even layer. Chill 30 minutes or until caramel is set.
Microwave morsels in a small glass bowl at HIGH 1 minute or until almost melted. Stir until smooth. Spread over caramel layer in pan. (The chocolate layer will be thin.) Chill 15 minutes or until chocolate is firm. Cut into 2-inch squares; if desired, cut each square into 2 triangles.
used all regular flour as i didn't have any white rice flour. taste was bland and texture was grainy. caramel mixture never got thick. even when i put it in the fridge, it never hardened and the chocolate topping cracked when cut. don't know why the name 'millionaire bars' cuz they don't taste a million worth.
Shortbread: try 2 1/4C flour, 1/2C sugar, 2 sticks butter. Melt butter then mix in flour and sugar. Press into bottom of pan. Any gluten free flour leaves the product more dry/crumbly. As does using butter that hasn't been melted. That's for pastry/pie crusts.
Caramel: works fine with only 1/2 stick butter.
Chocolate Ganache: try 1C semisweet chocolate chips. 2T butter, 1/4C heavy cream. Melt all ingredients in saucepan over low/med heat. Whisk often to keep from sticking, and to get mixture smooth and blended.
This is a sound recipe but I find these style/ingredient changes help make it a wonderful treat. Shortbread is a supporting flavor. The real stars are the chocolate and caramel.
Shortbread was very dry and crumbly when cutting. Could not even cut into triangles because they broke, and I had even baked less than suggested time. This recipe takes a lot of time and effort to make and isn't worth it tastewise.