3/4 cup egg whites, at room temperature (about 7 egg whites)
1 1/2 cups granulated sugar
1 teaspoon lime juice
1/2 teaspoon pure vanilla extract
Preheat the oven to 350 degrees F.
Spread the almonds on a baking sheet in a single layer. Toast until fragrant, stirring frequently to avoid burning the almonds, 5 to 7 minutes. Set aside to cool on a rack. If piping the meringues, roughly chop the almonds.
Raise the oven temperature to 450 degrees F. Line two large baking sheets with parchment paper or nonstick liners.
Using a stand mixer fitted with the whisk attachment or a hand beater, beat the egg whites on a low setting until foamy, about 1 minute. Increase the speed to medium low and add the sugar one tablespoon at a time until the meringue holds soft peaks, about 5 minutes. Add the lime juice and vanilla extract. Gradually increase the speed to high and continue to beat the meringue until it forms glossy, firm peaks, an additional 3 to 5 minutes. Gently fold in the cooled almonds.
Pipe the meringues onto the baking sheets in the desired shape using a pastry bag, or drop small mounds onto the sheets with a spoon. Place both baking sheets in the oven, close the door and immediately turn the oven off. Leave the oven unopened for at least 8 hours and up to 12 hours.