Place the hashbrowns on a baking sheet and follow the package instructions. After cooking, set the hashbrowns aside to cool.

Peel and slice the onions; cut the onions in half, then slice.

Place a skillet over medium-high heat, then add 2 tablespoons of EVOO and 2 tablespoons of unsalted butter.

When the butter has melted, add the sliced onions and sauté until they begin to brown.

Add sea salt and freshly cracked black peppercorns to taste.

Set the onions aside.

Preheat the oven to 350°F.

* Note: Do not add the potatoes to boiling water; start with cold water; this will avoid cooking the outside faster than the inside, which may result in a gluey or uneven texture.

Wash, scrub, and roughly peel two pounds each of Russet and Yukon potatoes.

Cut the potatoes into quarter rounds and add to a large stock pot.

Fill the pot about 3/4 full with water and add a couple of tablespoons of salt.

Bring the water to a boil and cook the potatoes 15-20 minutes, until fork-tender.

Pour off the water and return the potatoes to the pot, then add the 1 stick of unsalted butter, 3/4 cup of whole milk, and the shredded triple cheddar cheese mixture.

Use a potato masher to mash the potatoes until they are well combined and lump-free. *You can add more unsalted butter and milk to get the consistency you prefer.

Spoon the mashed potatoes into an oven-safe baking dish, then, using your fingers, break apart the cooled hash browns and arrange them evenly over the mashed potatoes.

Top with the sautéed onions and more cheese (about 1/2-1 cup of cheese).

Place onto the middle rack of the preheated 350°F oven and bake for 20 minutes.

Remove from the oven and serve warm.

We added chopped green onion on top for garnish.