Chocolate Revel Bars

from The Better Homes and Gardens New Cook Book

This recipe is halved to fit an 8-inch square pan. Double it if you want to use a 9x13 or 10x15-inch pan.

100g (1 stick minus 1 tablespoon) butter
200g (1 cup) packed brown sugar
1/2 teaspoon baking soda
1 large egg
1 teaspoon vanilla
155g (1-1/4 cups) all-purpose flour, sifted
122g (1-1/2 cups) quick-cooking rolled oats

Preheat the oven to 175°C (350°F). Line an 8-inch square pan with parchment paper cut to fit. Cream the butter until soft, then add the brown sugar and baking soda and cream until light and fluffy, scraping down the sides of the bowl occasionally. Add the egg and vanilla and beat until just combined. Using a strong wooden spoon, stir in the flour and rolled oats until just combined. Press two-thirds of the dough mixture in the bottom of the prepared pan.

Filling
12g (1 tablespoon) butter
200g (10-1/2 tablespoons or 7 ounces) sweetened condensed milk
125g (3/4 cup) semisweet chocolate chips

1 teaspoon vanilla

Combine the butter, condensed milk, and chocolate chips in a small heavy-bottomed saucepan or microwaveable bowl and place over low heat (or microwave on LOW power), stirring occasionally, until the chocolate has melted. Stir to combine and stir in the vanilla. Spread over the dough in the pan using an offset spatula and dot the surface with the remaining one-third of the dough (it's quite stiff, so use two spoons) irregularly in patches.Bake for 18-23 minutes or until the top is light brown (the filling will not be set at this point). Cool completely then cut into squares.