I've been itching to make these for months, and finally road-tested them this past weekend around the campfire. They were delicious, but for roasting they could stand to "set up" a bit more (get harder so leave them out uncovered for a day or so) so that they are not as volatile when molten.
Homemade Vanilla Marshmallows (adapted from recipe posted here on Brownie Points)
2 pkgs. unflavored gelatin softened in 1/4 c. plus 2 Tbs. water and 1 Tbs. pure vanilla extract (in the bowl of your mixer)
Combine in deep, heavy sauce pan and bring to boil with lid on: 1 1/2 c. sugar, 1/4 c. plus 2 Tbs. water, 1/2 c. plus 2 T. corn syrup, and 1/4 tsp. salt
While waiting, line an 8x8-inch pan with parchment paper and spray with oil.
Once hot mixture is boiling, remove lid and clip candy thermometer in pan. Cook without stirring until it reaches soft-ball stage (235-240-degrees F). Remove from heat, and very carefully and slowly, pour hot syrup into gelatin mixture while mixer is on medium-low speed. Once all is added, turn mixer on high and beat for a good eight minutes until light , fluffy and thick. Pour marshmallow fluff into prepared 8x8 pan and let set up for at least 10 hours. Dust with powdered sugar or mix of 1/2 pwd. sugar and 1/2 rice flour and cut with a pizza cutter into 32 squares (or you could make them smaller) . Dip all cut sides in sugar/flour or shake in gallon Ziploc with mixture.
The Brownie Points blog also has variations with flavored marshmallows, etc.