Early in the day or last thing at night, sift the sugar flour and salt together well.
Add the boiling water and stir until well blended.
Cover and leave until cold a 8 hours or overnight.
Later that day or next day,.
When you are ready to make your cake, preheat your oven to 250 degrees.
In a large bowl,( wiped down with vinegar just to make sure there are no oils) add the room temperature egg whites and beat until foamy.
Add the pinch of salt and the tartar, beat until stiff peaks but not dry.
While whites are beating, to the cold batter, add the two teaspoons baking powder, the almond and vanilla extracts, and stir well.
Once the whites are ready, fold in a little of it to lighten into the batter.
Fold in all the whites now into batter, trying to fold in well, and not deflate.
Place into a ungreased angel food tube pan.
Place into preheated 250 degrees oven and bake for 15 minutes on the medium centre rack.
After 15 minutes increase heat without opening door to 300 degrees and bake for another 20 minutes.
After the 20 minutes increase heat to 350 degrees, without opening the door, and finish baking for 15 minutes.
Test cake to see if its completely cooked with a long skewer.
If done remove, if not reduce the heat to 325 and continue until tester shows done. I have never had to leave in any longer but all ovens are different. Also please use a timer for each of the oven temperatures when increasing.
When done, remove to wire rack.
Turn upside down until cool, and then run knife around edges and release cake.
I do have to run the knife around all edges then remove the bottom part of the pan and then again under the bottom.
I always use a two piece tube pan for this recipe.
The almond and vanilla can be as original recipe one teaspoon each or more as I have increased . The combination of both is a must in the recipe.