Peel or leave skins on the Yukon gold potatoes. Add cubed potatoes into a pot, add water to cover, 2 tsp salt, and bring to a boil. Cook for 20 minutes or until potatoes are tender. Drain.

Mash drained potatoes with a potato masher. Add warm milk, 5 Tbsp melted butter, 1 tsp salt, and 1/2 tsp pepper. Blend using a hand mixer.

In a large bowl, stir together cold mashed potatoes, flour, cheese, and eggs.

The dough should be able to press into a patty without sticking to your hands, add flour until it reaches this consistency.

Once the dough is the right consistency, knead in the ham, onion, garlic, salt, and pepper.

Start by placing a large skillet on the stove over medium heat. Pour about 1/3 cup of vegetable oil, or just enough to thinly coat the bottom of the skillet. Allow oil to heat up—it should be hot but not smoking. Use an ice cream scoop to portion out the dough and carefully place it into the hot oil. Flatten the dough gently with the back of the scoop or a spatula to form a patty shape. Make sure to space out the patties and cook them in batches if necessary to avoid overcrowding the skillet, which can lead to uneven cooking.

Cook for 2 minutes per side or until golden brown. Drain on a paper towel-lined sheet.

Sprinkle with extra cheese, sour cream, and green onions to serve.