INSTRUCTIONS
1. Preheat oven to 350 °F .
2. Bring a large pot of lightly salted water to a boil. Add potatoes, and cook until tender but firm, about 15 minutes; drain.
3. In a large bowl, mash potatoes with the butter and milk.
4. Add the mozzarella and grated shallot. Gently mix.
5. Season with salt and pepper. Transfer to a 2 quart casserole dish.
6. Bake 1 hour in the preheated oven, or until puffy and lightly browned.
