If serving immediatley, preheat oven to 400 degrees.
Cut potatoes into quarters and place in a large pot. Add enough cold water to cover the top of the potatoes about an inch. Bring to a boil and reduce to simmer. Simmer until fork tender, about 10 minutes. Drain and return to pot.
In the pot along with the potatoes, add in the butter, ricotta, parmesan, milk, salt, and garlic powder. Mash with a potato masher until desired consistency is reached. Spoon potato mixture into a greased casserole dish and smooth the top.
For the topping, in a small bowl mix together the parmesan and breadcrumbs. Pour on top of potatoes and drizzle with olive oil. Cover with foil and bake for 20 minutes. Remove foil and bake for another 5 minutes until crust is golden.
Notes
Red potatoes are a great potato to use here because it is thin-skinned and doesn't need to be peeled. You can use other types of potatoes, just peel the skin first.
Always fill the pot of potatoes with cold water. This will ensure more even cooking.
Drain the potatoes and add the remaining ingredients directly to the pot. The warmth of the pot will help to warm all of the other ingredients, plus, less mess!
If desired, you can skip the baking dish and just serve the potatoes as is without the topping.
Serving a large crowd? You can easily make a double batch of this recipe and serve in a large dish.
To make ahead, prepare the entire dish without baking, cover and refrigerate. When ready to bake, add an additional 10-15 minutes to the baking time.