In a medium saucepan, combine fresh lemon juice and simple syrup. You can adjust the simple syrup to achieve your preferred level of sweetness. Mix well.
Pour in the gelatin to the simple syrup mixture. Allow the gelatin to soak for 2 minutes. Gently heat over low heat. Stir continuously until the gelatin is completely dissolved (about 2-5 minutes). Avoid boiling to preserve the flavors.
Remove the saucepan from the heat, and add the gin and champagne, stirring well to blend.
Lightly grease a loaf pan or line a loaf pan in plastic wrap. Then, pour the jello mixture in the loaf pan. Chill in the refrigerator until the gelatin is fully set and firm. This typically takes a few hours (minimum of 2) or overnight.
Once set, carefully turn over and remove firm gelatin onto parchment paper. Then, slice carefully into rectangles or squares.
Optional: Garnish with edible gold leaf using a paintbrush or tweezers.
Notes
Gold leaf crumbles and sticks to things (like fingers) easily so be gentle. Just pull off tiny corners with the brush. (They will stick). Then, place them gently on top of the gelée squares. Refer to the blog post for more tips and tricks.