Caramelized Cashew Toffee Cake

Ingredients:
2 tbsp water
2 tbsp nescafe coffee
115g semi-sweet chocolate ~ chopped
1/4 cup / 60g vegetable oil
1/4 cup / 57g unsalted butter
1-1/4 cup / 150g AP flour
1 cup / 200g sugar
1/4 tsp baking soda
1/4 tsp baking powder
1/4 tsp salt
2 eggs
1/4 cup / 65g plain yogurt
1 tsp vanilla

Topping
1-3/4 cup / 240g roasted cashew nuts ~ chopped roughly
1/4 cup / 65ml evaporate milk
1 tsp nescafe coffee
1/2 cup / 113g unsalted butter
3/4 cup / 150g sugar
3 tbsp AP flour
1/4 tsp salt

Directions:

1. Preheat oven to 180 deg C.  Grease the side of sheetpan (19"x13") with oil/butter & line a bottom with parchment paper.
2. In a small pot, add the water & coffee; stir over medium heat until mostly dissolved.  Add chocolate, oil, butter & stir until melted & smooth.  Remove from heat & set aside.
3. In a mixing bowl, whisk together all the dry ingredients until there is no more clumps. In another bowl, whisk together all the wet ingredients.  
4. Pour the chocolate mixture into the dry ingredients & stir with spatula until the flour is completely moistened.  Then add wet ingredients & whisk until smooth.  Once the batter is smooth, pour into the prepared pan & bake for 18-20 mins or until test pick inserted into the middle comes out clean.  Let cool while making the topping.
5. Topping: In small pot set medium/low heat, stir together milk & coffee until dissolved.  Add butter & cook until it's melted.  Stir occasionally.
6. While the butter is melting, whisk together flour & sugar well combined.  Then add dry mixture into the melted butter.  Constantly stir.
7. Once boiled, turn off & add chopped cashew nuts.  Pour the topping over the cake & spread evenly to cover the entire cake.
8. Turn oven broiler on "low" & broil for 3-5 mins until the topping has caramelized & browned.
9. Once cooled, loosed the side of the cake.  Place a cutting board on top of the cake & flip upside down.  Cut & the cake use a knife with long blade to "mark" by cutting through & stop when the blade reaches cashews.
10. Then use a sharp Chief knife, go into same cuts with one firm press.