Ingredients
Method
Preparation
- Preheat the oven to 350°F and grease a 9x13-inch casserole dish.
- Place the peeled and quartered potatoes in a large pot, cover with salted water, and boil until tender, about 15 minutes. Drain well.
- Melt 4 tablespoons of butter in a skillet over medium heat. Add diced onion and celery; cook for about 20 minutes until soft and golden.
- Toast the bread cubes in a separate pan until golden.
Assembly
- Mash the drained potatoes in a large bowl. Stir in the cooked onion and celery, toasted bread, remaining 6 tablespoons of butter, milk, and beaten egg. Season with kosher salt to taste.
- Spread the mixture in the prepared casserole dish.
Baking
- Bake for about 45 minutes until the top is golden brown and the filling is hot. Let stand briefly before serving.
Make Ahead and Reheat
- Assemble the filling in the casserole dish and refrigerate for up to 2 days before baking. To reheat, cover and warm at 350°F for 10 to 15 minutes.
Notes
Pairs well with roasted chicken, turkey, baked ham, or pork chops. Can be assembled ahead for convenience.
