Caramel & Walnut Cake

Cake:

1. Grease a cake pan and sprinkle it with flour.
2. Beat the butter with the sugar, until it is very smooth.
3. Add the eggs, one at a time, the egg yolk, and beat well between each addition.
4. Add the flour and finally the caramel and beat some more.
5. Pour the batter into the pan and bake at 180ºC or 350ºF for about 45 minutes.
6. Let it cool, unmold and place it on a serving dish.

Topping:

1. In a pan over low heat, heat the condensed milk with the caramel and the oil and stir with a wire whisk, and then continue to stir with a wooden spoon, when the mixture leaves tracks from the wooden spoon, remove it from the heat and pour it over the cake.
2. Let it cool and garnish/decorate with the walnut pieces.