My mom made this dish (sometimes just with vegetables, hold breadcrumbs) as a favorite side dish when I was little. Over the years she caught on that I loved it more than anything she made to go with it. After years of ignoring the chicken or pork on the plate she finally started preparing for me as a main dish, center plate. I love this as a meat-free main course.
Preheat oven to 375°F. Pour about 2 tablespoons olive oil into casserole dish and add about 2 tablespoons melted butter. Add potatoes in overlapping concentric circles to cover the bottom of the pan, moving the oil and butter around the potatoes as you place them. Pat into place when an even layer is formed and season with salt and pepper. Transfer to oven and roast potatoes until lightly golden at edges, about 20 minutes. Remove and cool.
Combine breadcrumbs, cheese, parsley, salt and pepper with remaining 2 tablespoons melted butter.