1 cup boiling water
1/2 (3 ounce) package lemon-flavored gelatin mix (such as Jell-O®)
1/4 cup gin
1 3/4 cups sparkling wine, divided
3 (.25 ounce) envelopes unflavored gelatin
1 drop red food coloring
Pour boiling water over lemon-flavored gelatin in a glass measuring cup; stir to combine. Stir in gin. Pour mixture into sixteen 2-ounce cups. Arrange cups in muffin tins, tilted to one side.
Refrigerate until set, about 4 hours.
Combine 1 1/4 cup sparkling wine and unflavored gelatin in a small pot. Let sit, about 3 minutes. Heat over low heat, stirring constantly, until gelatin is dissolved, 3 to 5 minutes. Add remaining 1/2 cup wine and food coloring; stir to combine.
Remove muffin tins from refrigerator. Set cups upright; pour wine mixture over lemon mixture.
Return to the refrigerator and chill until set, about 4 hours.