Pre-heat oven to 350 F. (175 C.), and fill a large pot with enough water to cover your potatoes. Place pot on a burner and turn to high heat. Remove cloves from a full head of garlic, peel the skins, then slice off the little ends.
Cut 6 potatoes into smaller pieces. They’ll boil faster that way.
Grate 2 tbsp. of parmesan cheese if you want to make the baked top even more crispy. Set aside.
Place garlic cloves on tinfoil and drizzle with 1 tbsp. olive oil. Wrap the foil around the cloves loosely and place on a baking sheet. Place in the oven and roast for 20 minutes at 350 F. (175 C.).
Once the water is boiling, carefully place the cut potatoes in the pot. Allow to boil for 20-25 minutes until you can easily poke through a piece with a fork.
Remove garlic from the oven and set aside until the potatoes are done. Raise the oven temperature to 400 F. (205 C.) for when you’re ready to bake the mashed potatoes.
Pour the water out of the pot, keeping the potatoes in. Add roasted garlic, 4½ oz. (133 ml.) herbed goat cheese, 4 oz. (118 ml.) heavy cream, 2 oz. (60 ml.) salted butter, and salt & pepper to taste. Mash and mix with a hand masher, just until it’s nice, fluffy and creamy – about 3 minutes. Be careful not to over-mash and mix or it will become an unappetizing, glue-like texture.
Grease an 8”x8” pyrex baking dish with butter, and pour your mashed potatoes in. Spread evenly, but leave some hills and valleys in the potatoes – it makes for a tastier baked top.
Beat an egg and use a pastry brush to spread it onto the potatoes in a thin layer. Sprinkle parmesan on top of the potatoes evenly. Bake at 400 F. (205 C.) for 20 minutes on the top rack. Remove and serve.