Seems like there are two theories on homemade marshmallows - one with egg whites, the other without. After trying both, I'd say that the ones without egg whites come close to the kind you buy at the grocery and the ones with egg whites come close to the kind you might find in pinwheel cookies. I guess it's up to you which one you like best.
I chose the ones with egg whites (this one is from MarthaStewart.com - Momma Reiner's). I added peppermint extract and, after a couple of experiments, changed the order of when the gelatin was added.
Nonstick cooking spray
2 tablespoons plus 1/2 teaspoon unflavored gelatin (3 packets)
2 cups sugar
1/2 cup light corn syrup
1/2 cup hot water
1/4 teaspoon salt
2 large egg whites
1 teaspoon pure vanilla extract
1 teaspoon peppermint extract
Powdered Sugar for dusting
1. Lightly spray a 9-by-13-inch dish or pan with nonstick cooking spray.
2. Sprinkle gelatin over a small bowl filled with 1/2 cup cold water; let stand to soften.
3. In a heavy bottomed saucepan, mix together sugar, corn syrup, hot water, and salt. Place over medium heat and cook, stirring, until sugar has dissolved. Continue cooking, without stirring, until mixture reaches the soft-ball stage, about 240 degrees on a candy thermometer. Remove from heat.
4. While that is heating, in the bowl of an electric mixer fitted with the whisk attachment, beat egg whites on high speed until stiff peaks form.
5. Add gelatin mixture to egg whites.
6. With the mixer running, slowly add sugar mixture.
7. Add vanilla and peppermint and continue beating for 10-12 minutes until the mixture is not runny and looks like marshmallow.
8. Transfer marshmallow mixture to prepared baking dish and spread evenly. Spray a piece of parchment paper with nonstick cooking spray and cover marshmallow. Let stand overnight.
9. Remove parchment paper and invert marshmallow onto work surface. Trim 1/4-inch from edges of marshmallow. Cut marshmallows into 1 1/2-inch squares. Put marshmallows in a bowl and lightly sprinkly with powdered sugar to coat.
10. Dip in melted chocolate. (And I sprinkled them with Christmas non pariels.