2 pounds russet potatoes, peeled, halved lengthwise, and sliced 1/4 inch thick
Salt and pepper to taste
1 ounce Parmesan cheese, grated (1/2 cup)
cup chopped fresh chives
1 large egg yolk ?plus 2 large eggs
2 cups panko bread crumbs
1 cup vegetable oil
Sour cream

Place potatoes in medium saucepan and add water to cover by 1 inch, then stir in 1 tablespoon salt.
Bring to boil over high heat.
Reduce heat to medium-low and simmer until tip of paring knife inserted into potatoes meets no resistance, 8 to 10 minutes.
Drain potatoes and return to saucepan; let cool for 5 minutes.
Add Parmesan, chives, egg yolk, 3/4 teaspoon salt, and 1/4 teaspoon pepper to cooled potatoes.
Using potato masher, mash until smooth and well combined.
Transfer potato mixture to bowl and refrigerate until completely cool, about 1 hour.
Beat remaining 2 eggs together in shallow dish. Place panko in second shallow dish.
Divide potato mixture into 8 equal portions (about 1/2 cup each) and shape into 3-inch-diameter cakes, about 3/4 inch thick.
Working with 1 cake at a time, carefully dip cakes in egg mixture, turning to coat both sides and allowing excess to drip off;
then coat with panko, pressing gently to adhere.
Transfer to plate and let sit for 5 minutes.
Line large plate with paper towels.
Heat 1/2 cup oil in 12-inch nonstick skillet over medium-high heat until shimmering.
Place 4 cakes in skillet and cook until deep golden brown on first side, about 3 minutes.
Using 2 spatulas, carefully flip cakes and continue to cook until deep golden brown on second side,
about 2 minutes longer, gently pressing on cakes with spatula for even browning.
Transfer cakes to prepared plate. Discard oil and wipe out skillet with paper towels.
Repeat with remaining 1/2 cup oil and remaining 4 cakes.
Serve with sour cream.

Notes:
Using two spatulas to flip the cakes helps prevent splattering.
The cooked mashed potatoes need to chill in the refrigerator for 1 hour, which makes it easier to form the cakes.

Cooks Country