Boil water in a large pot for lasagna noodles. Cook 3 minutes less than suggested time. Drain. Set aside.
Slice potatoes with mandolin at a medium thickness.
You can either boil or roast the sweet potatoes. Boil slices in pot of boiling water for about 2-3 minutes. Drain and paper towel dry. You can roast in oven at 375 for 10 minutes, turning once. I prefer roasted.)
In a small frying pan, saute butter and shallots until softened.
Mix ricotta cheese and 1/4 cup goat cheese with parsley, one egg, salt and pepper, nutmeg, half of the parmigiano reggiano cheese.
Assemble: Layer pasta, ricotta cheese, sliced sweet potatoes, top with a small amount of the reserved shallots, pinch fresh thyme, mozzarella cheese and 1/4 cup of goat cheese randomly.
You will make three layers.
The final layer will be covered lasagna noodle, mozzarella cheese, goat cheese, sweet potatoes and fresh thyme.
Bake for 30 minutes at 375 degrees F. Add Parmesan cheese. Bake another 10 minutes.
Notes
I used a homemade semolina pasta in this dish, but you can use regular lasagna noodles, undercooked by about 3 minutes.