A decadent way to use up egg whites!
Cream butter and brown sugar. Add egg and vanilla, then cocoa, flour and baking powder. Push into the bottom of a slice tin or large square cake tin. Heads up, unlike a 'normal' slice base, this one is basically cookie dough so don't try and smear it out with a bottom of a spoon, it will be a right pain, get your hands in there and you'll have it sorted in a jiffy. Smear the nutella evenly over the base. Rinse out your base bowl and use the mixer to beat the bajeesus out of the egg whites. Once they are soft peaks, add the sugar and beat until stiff peaks form. Fold through the coconut and spread on top of slice. Bake at 180 deg cel until the top is nicely browned and the meringue feels firm-ish in the middle.
I use this recipe to use up leftover egg whites. Today I used 4 but it wouldn't make a great deal of difference if you only used 3, certainly don't bother separating another egg specially! If you are only using 3 or they are smaller eggs, maybe consider easing back on the coconut a bit.
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