Preheat oven to 275° F. Prepare 2 cookie sheets with aluminum foil, shiny side down.
In the bowl of your mixer, using the whisk attachment on a medium speed, beat egg whites and salt until frothy, about 1-2 minutes.
Add vinegar and beat until soft peaks form, about 2 minutes. Slowly beat in sugar and cream of tartar until stiff peaks form, about 2-3 minutes.
Beat in vanilla flavoring until incorporated, about 1 minute.
Spoon mixture into piping bags and pipe into desired shape onto the cookie sheets. Leave about 1-2 inches apart, they don't spread.
Sprinkle the sprinkles onto the meringue while still wet.
Bake 20-30 minutes, turning cookie sheets after first 10-15 minutes. They may crack slightly and that's okay. But you don't want them browning or they will be tough. This is why the time varies, based on the size of your meringues.
Cool and serve. Store airtight for a few days if needed.
Notes
* To get your eggs room temp in about 10 minutes, place them in a bowl of warm (not hot) water.**For baker's sugar I take granulated sugar and pulse it in the processor for about 30 secs to a minute.- Timing: Make sure you don't over bake these as meringues should have a hard outside and soft inside like a marshmallow center.- Decorating: These are fun to shape how you want and decorate with sprinkles. You can also use them on top of cakes as decor themselves.- Bowl and whisk: Your bowl should be super clean and dry. This helps when whisking the eggs to the best consistency.