So I haven't written in forever and, the longer it went, the harder it was to come up with something that justified a post. But I finally came up with something!
3 1/2 envelopes (2 tablespoons plus 2 1/2 teaspoons) unflavored gelatin
1 cup strained strawberry puree, divided
2 cups granulated sugar (cane sugar worked just fine)
1/2 cup light corn syrup
1/4 teaspoon salt
2 reconstituted egg whites (reconstituted w a 50/50 mix of water and strawberry juice)
1 tablespoon vanilla
Oil bottom and sides of a 13- by 9- by 2-inch rectangular metal baking pan and dust bottom and sides with some confectioners’ sugar.
In bowl of a standing electric mixer or in a large bowl sprinkle gelatin over 1/2 cup cold strawberry puree, and let stand to soften.
In a 3-quart heavy saucepan cook granulated sugar, corn syrup, second 1/2 cup of strawberry puree, and salt over low heat, stirring with a wooden spoon, until sugar is dissolved. Increase heat to moderate and boil mixture, without stirring, until a candy or digital thermometer registers 240°F, about 12 minutes. Remove pan from heat and pour sugar mixture over gelatin mixture, stirring until gelatin is dissolved.
With standing or a hand-held electric mixer beat mixture on high speed until white, thick, and nearly tripled in volume, about six minutes if using standing mixer or about 10 minutes if using hand-held mixer. (Some reviewers felt this took even longer with a hand mixer, but still eventually whipped up nicely.)
In separate medium bowl with cleaned beaters beat egg whites (or reconstituted powdered whites) until they just hold stiff peaks. Beat whites and vanilla (or your choice of flavoring) into sugar mixture until just combined. Pour mixture into baking pan and don’t fret if you don’t get it all out (learning from my mess of a first round). Chill marshmallow, uncovered, until firm, at least three hours, and up to one day.The result is a lovely, pale pink marshmallow with a strong strawberry/vanilla flavor (which is achieved with NO artificial flavors or colors - at least none until the colored sugar covers them! LOL)