I had no reason to think this was going to work. My searching didn't turn up any recipes that combined whipped egg whites and fruit pulp which is usually a pretty good indication that it's not a good idea. But I had everything I needed lying around so I thought I'd give it a try just to see what would happen.
pulp from several small black sapotes
1 banana, frozen and defrosted
1-3 Tablespoons sugar depending on how sweet your fruit is
1 pinch salt
1 teaspoon vanilla
5 Tablespoons whole wheat pastry flour
some agave nectar
2/3 cup egg whites
0. Preheat oven to 300 degrees.
1. Blend the fruit. Add the sugar and vanilla and blend some more. Stir in the flour.
2. Beat the egg whites to stiff peaks. Stir 1/3 of the egg whites into the fruit mixture to lighten. Fold in the second third. Fold in the third third. Check for sweetness. Fold in agave nectar until the flavors pop.
3. Using a coffee or small ice cream scoop, dispense dollops of batter onto cookie sheets prepared using your most extreme non-stick procedure. Bake for 40 minutes, turning halfway through. Take them out, try one, discover it's raw in the center and put them back in for 15 minutes at 350 degrees.
For my second batch I found 25 minutes at 350 degrees worked well, but the hour of sitting around deflated the cookies which may have had some effect so use your best judgement.
I call these cookies, but only because I can't think of a better word for them. They've got the soft squishy/chewy texture of angel's food cake. Actually many are partially pre-squished due to troubles I had getting them off the parchment paper I baked them on.
Fresh out of the oven they were a little crisp around the edges, but that fades. There's still a little crystal-crunch from the sugar which I actually like, but you may want to avoid by using confectioner's sugar.
Despite having substantially more sapote than banana, the flavor is predominantly caramelized banana. The sapote rounds it out, but it could be mistaken for a hint of chocolate. Pretty tasty. Maybe it could use a little acid to brighten it up--a lemon sugar glaze maybe?