Spray a 9x13” rimmed baking sheet with oil, line with parchment paper and set aside.

Preheat oven to 220˚C (425˚F)

Place cashews, icing sugar, flour and salt in a food processor and grind till the cashews are fine

Combine cashew mixture with eggs in a large bowl beat for 2 minutes till well combined, set aside.

In the bowl of a stand-mixer fitted with the whisk attachment (alternately you could use a hand held mixer) combine the egg whites and granulated sugar. Whip till you have a meringue that is stiff and glossy.

Fold the meringue into the cashew batter followed by the melted butter being careful not to overmix.

Spread into baking pan and bake for 5 to 8 minutes till the top is nicely browned.

Remove from oven, invert onto a cooling rack, peel off parchment and let cool completely