Place colander in a medium bowl. Line colander with 4 layers of cheesecloth, allowing cheesecloth to extend over edge of colander. Spoon yogurt into colander. Cover loosely with plastic wrap; refrigerate 12 hours. Spoon yogurt cheese into a medium bowl; discard liquid.
Sprinkle gelatin over 1 tablespoon water in a microwave-safe bowl; let stand 1 minute. Microwave at high 15 seconds, stirring until gelatin dissolves. Let cool slightly (about 3 minutes); whisk gelatin mixture into yogurt cheese. Stir in peanut butter and 1 tablespoon peanuts; set aside.
Combine sugar and remaining water in a microwave-safe bowl; stir well. Microwave at high 3 minutes or until mixture boils, stirring every minute; set aside.
Beat egg whites and salt at high speed of a mixer until foamy. Gradually pour hot sugar syrup into egg white mixture, beating at medium speed; then beat at high speed until stiff peaks form.
Gently fold egg white mixture into yogurt cheese mixture. Spoon 1 cup into each of 4 (8-ounce) stemmed glasses; sprinkle with remaining peanuts. Cover; chill at least 3 hours.