Blanch and grind almonds, this is a good opportunity to make a big batch so you have extra for other recipes. See this thread for tips on blanching and grinding almonds: Nut Meals and Flours.
Preheat oven to 180 C (350F).
Whisk the dry ingredients in a medium to large bowl. In a smaller bowl whisk the eggs, vanilla and almond essence then add the butter mixture and whisk well. Add wet mixture to dry mixture and stir, this will be a sloppy batter.
Next either grease or line a metal springform pan or use silicon. I used the silicon and it worked fine for this. Pour mixture in and spread evenly then sprinkle almond flakes over the top of the cake.
Chuck in oven for about 40 minutes or until cake springs back slowly. Let cool in pan.
Notes: Belinda recommends that you eat this at room temperature or slightly warmed, though it still tastes good cold just chewy like candy. Keeps in the fridge for up to a week (won't last that long!) and freezes well for 3 weeks.