Start by making a batch of lemon curd. While the Lemon Curd (24 ounce) is heating on the stove, mix Gelatin Powder (1 teaspoon) with 1 tablespoon water. Let the gelatin bloom while you finish heating and whisking the lemon curd until thickened.
Add the bloomed gelatin to the lemon curd and whisk thoroughly. Strain the curd and let cool to room temperature and then transfer to the fridge to chill for at least 2 hours.
For the crepes, add Egg (3), Milk (10 fluid ounce), Unsalted Butter (4 tablespoon), Honey (2 tablespoon), Vanilla Extract (1 1/2 teaspoon), Gum-Free Gluten-Free Flour (1 cup), and Salt (1/8 teaspoon) to a blender jar and blend for about 10 seconds.
Pour the crepe batter through a sieve into a bowl, whisk in the Poppy Seeds (2 tablespoon), cover and refrigerate for at least 2 hours.
Once the crepe batter has chilled in refrigerator, heat a 7-inch crepe pan over medium low heat and add a scant 1/4 cup of crepe batter the heated pan, swirling the pan to evenly coat it with the batter.
Cook the crepe for approximately 1 1/2 to 2 minutes and then flip and cook for another 60 seconds.
Repeat until you have used all of the crepe batter. You should end up with 15 to 17 crepes.
For the candied lemon garnish, prepare an ice bath in a medium sized bowl.
Bring about 4 cups of water to a boil in a medium saucepan and blanch sliced Lemon (1) for 1 minute. Remove lemon slices, placing them into the ice bath.
Heat Water (1/2 cup) and Honey (1/2 cup) in a medium saucepan until simmering, turn down heat so that the syrup is barely bubbling. Add chilled lemon slices to the saucepan in one even layer. Cook for approximately 1 hour, until the rinds are clear.
To assemble the cake, whip Heavy Cream (1 cup) until medium soft peaks and fold whipped cream into the chilled lemon curd.
Spread a bit of the filling onto the plate or cake stand that you will be building the crepe cake on and lay the first crepe on top of it. This acts like glue to keep the base of the crepe cake from moving.
Add 1/4 cup of filling to the crepe and spread evenly and continue with another crepe followed by 1/4 cup of filling until you reach the final crepe.
Cover crepe cake with plastic wrap and refrigerate for at least 12 hours or overnight.
When ready to serve, whip Whipping Cream (1/2 cup) into soft peaks, top crepe cake with whipped cream and candied lemon slices.