Mashed Potato Casserole

Ingredients

3.5 lb potatoes
1 tbsp cooking / kosher salt , for cooking potatoes
2/3 cup milk
2/3 cup EXTRA milk , for make-ahead option only
5 tbsp unsalted butter , cut into 1cm / 1/2″ cubes
1/2 cup sour cream (or yogurt), full fat best
1 tsp cooking/kosher salt , or to taste
1 1/2 cups (tightly packed) mozzarella , freshly shredded
1 cup (tightly packed) Red Leicester, cheddar or other flavored cheese
6 oz bacon (streaky), chopped
1/4 cup green onion , finely sliced

Directions

COOK BACON:
Place bacon in a cold non-stick pan over medium heat (no oil). As the pan heats up the bacon fat will melt. Once you see some melted bacon fat, turn the heat up to medium high and stir for 3 minute or until golden. Drain on paper towels.

MASH:
Peel then cut potatoes into 1″ chunks.

Place in a large pot and cover with water so it’s 4” above the potatoes. Add 1 tablespoon salt. Bring to a boil over high heat then reduce heat so it’s simmering rapidly. Cook 15 minutes or until potatoes are very soft.

Drain well, then return into pot. Leave for 1 minute, shaking pot every now and then, to encourage evaporation of water.

Add milk (including EXTRA milk if making-ahead), butter, sour cream and 1 tsp salt. Mash until smooth. (Do not use food processor, blender or beater, makes it gluey!)

Preheat oven to 400°F.

Spread the potato in a 2 quart baking dish. Smooth the surface.

Sprinkle potato with the cheeses, then bacon.

Bake covered – Cover loosely with foil. Bake for 20 minutes covered.

Remove foil then bake a further 10 minutes until the cheese is bubbly and golden.

Sprinkle with green onion then serve! It stays warm for a good 20 minutes thanks to that protective layer of cheese. Oh, the powers of cheese!

MAKE-AHEAD DIRECTIONS:
Allow to fully cool on the counter then cover tightly with cling wrap and refrigerate.
Take out onto counter 2 hours prior to reheating. Reheat in 400 oven for 35 minutes.