Preheat the oven to 225F and line a baking tray with a sheet of parchment paper or silpat.
In a stand mixer with a whisk attachment beat on medium speed the egg whites and salt, once they are foamy slowly add the sugar a tablespoon at a time letting beat for a few seconds in-between additions. When you’ve added all the sugar turn up the speed to high and beat until you have stiff glossy peaks.
Add the cornstarch, vinegar, rosewater and food coloring if using, mix on low until just combined. Scrap down the bowl with a spatula to ensure everything is evenly combined.
Using a large disher or two spoons dollop the meringue onto a tray and shape them into little nests, you want a small divot in the middle to hold your cream and fruit when you serve. Sprinkle the meringues with the chopped pistachios.
Bake at 225F for 1 hour to 1 ½ hours until they are firm to the touch. Turn off the oven and open the door a crack, let cool for 1 hour.
Dollop each meringue with whipped cream, sliced apricots and an additional sprinkle of chopped pistachios.