- Preheat the oven to 260 degrees F. and line three baking sheets with parchment paper.
- Spread the sugar onto a parchment lined SHEET BAKING PAN and warm it in the oven for about 5 minutes.
- Pour the egg whites into the bowl of an electric stand mixer fitted with the whisk attachment. Whisk the egg whites on high speed until they form stiff peaks.
- When the egg whites are stiff, add the warm sugar, a tablespoon at a time, and continue to whisk. Thoroughly whisk in each tablespoon before adding more sugar.
- Once all the sugar has been added, whisk the egg whites until stiff and glossy, about 5 to 6 more minutes.
- Add the vinegar, vanilla and 3 drops of the green food coloring gel to the egg whites, and whisk for 2 additional minutes (if not green enough, add another drop or 2 until desired color).
- Use a large (1 1/2”) cookie scoop, drop 6 meringues onto each baking tray.
- Place the trays in the preheated oven for 30 minutes. Turn off the oven and leave the meringues to dry out for a few hours, or overnight.
- Brush the back of a candy heart with a tiny bit of water to adhere a heart gem onto each meringue.
- Remove the meringues from the parchment and store in an airtight container for 2 to 3 days.
Super fine sugar, a.k.a. castor sugar, may be made with regular sugar. Simply grind the sugar in a spice blender or food processor until it is ground into a finer consistency--finer sugar dissolves more quickly and consistently. The keys to awesome meringues are simple: do not make on humid days, use a super clean bowl and mixing whisk, separate eggs when cold but wait to use them until they are room temperature, and add the sugar slowly, one tablespoon at a time and incorporated until the whites are shiny and stiff. This is an incredibly flexible recipe that may be doubled or tripled by simply weighing egg whites and doubling the amount of sugar (if 150 ml egg whites, then add 300 gr sugar)—no need to adjust the vinegar or vanilla.