Preheat oven to 350 degrees F and line a baking sheet with parchment paper.
In a large bowl, add the almond flour, coconut flour, tapioca flour, coconut sugar, baking soda and sea salt. Mix to combine.
In a small bowl. Add egg and whisk. Add vanilla and mix to combine.
Add the wet ingredients into the dry ingredients and start to mix with spatula. Add in small pieces of butter at a time and continue to mix until everything is combined.
Fold in chocolate chunks.
Form dough into balls (think a little bit bigger than a golf ball size) and press 1 marshmallow into the ball then re-shape into a ball again making sure the marshmallows are almost all covered. It's ok if you see them poking out a bit!
Place on baking sheet and gently press down a little bit (don't flatten). You want them to be big.
Bake for 10-11 minutes. You want them to be golden brown at the bottom and slightly golden brown on top. They will be soft and look a little undercooked but they will be perfect!
Sprinkle flakey salt on top (if using).
Cool for 5-10 minutes before eating.