I have been trying to make macaroons recently and one thing that is not mentioned in blogs and recipes is where should I put the meringue/almond lava mixture while the first tray is drying/baking. A recipe with about 100g of egg whites usually yields 3 trays for me and I only have 2 (3 trays but they are stacked during baking). Do I just let it stay in the piping bag while I wait for the first tray to be done? Will the mixture become runnier? Will stuff separate?