I've found DOZENS of them online.
- Example one.
- Example two.
- Example three. This one seems promising.
- Example Four. Another one that looks interesting
- Example five. This is the most well researched!
Now, according to example five:
"What Tolkien says about Lembas
- They contain honey
- they are light-colored on the inside and light brown crust
- they are thin and regular-shaped. This implies they were made on some kind of griddle iron. The closest modern equivalent is a Krumkake iron. I used a pizzelle iron
Some other things we can guess.
- They contain the fruit and maybe the flower-water of the Mallorn tree. I substituted oranges, although kumquats or a hand of Buddha fruit might be better.
- They probably had some kind of finely ground light-colored nut in them. I used almonds.
- They contained some kind of nourishing flour. I used semolina flour, which is a more primitive flour, and also more nourishing.
- Galadriel probably used some kind of grinder to refine the ingredients. I used a blender."