The recipe I've been using for making this classic cake seems well-proven by lots of Thai food bloggers. Thus, needless to say how wonderful it is..
Toffee cake ( adapted from here )
94 g self raising flour
1.5 tbsps coffee powder
1.5 tbsps Cocoa powder
110 g caster sugar
1.5 teaspoons baking powder
110 g butter, melted
3 large eggs
1/ 4 teaspoon salt
150 g butter
60 g evaporated milk
110 g sugar
1/4 tsp salt
1 tsp coffee powder
3.5 tbsps self raising flour
170 g salted ( roasted ) cashew nuts
Make the cake : Preheat the oven to 180c. Lightly grease 8 inches square cake tin and line with parchment paper. Sift together the flour+baking powder+salt+cocoa powder+coffee powder into a bowl and set aside.
In a mixing bowl, beat/whisk the eggs on high speed until well risen. Then gradually add the sugar ( a tablespoon at a time ) while the machine is still running on high speed and continue beating for about 10-15 minutes until the batter reaches the ribbon stage.
Fold in the flour mixture. Mix gently with spatula until incorpaerated. Add lukewarm melted butter and fold gently to mix everything until blended. Pour the batter into the prepared tin. Bake in the preheated oven for 20-25 minutes. Leave to cool in the tin for 10-15 minutes and turn the cake out onto wire rack and let it cool to room temperature ( or you can leave it cool in the tin without turning out if the bottom is not overbaked like mine ) .
When the cake is cool, put it back into the tin with parchment paper , make the topping : Mix all ingredients except the flour and nuts in a medium bowl and let them melt over low heat on the stove top. Add the flour and keep whisking until the flour cooked and the mixture smooth. Add in the nuts and mix throughly. Off the heat , and spread the the topping over the cake. Bake in the preheated oven ( 200c ) for 15-20 minutes until the topping is dry and nicely brown..Let it cool in the tin before turning onto the cutting board ( with the top facing down ) and slice into pieces.