Grate the potatoes and finely chop the green onions.

In a large bowl, combine the grated potatoes, chopped green onions, eggs, parsley, garlic, seasoning salt, black pepper, and cayenne pepper (if using). Mix well.

Heat 2 tablespoons of butter and 1 tablespoon of olive oil in a large skillet over medium heat until hot.

Spread the potato mixture evenly in the skillet, pressing down with the back of a spoon.

Cook over medium-high heat for 2-3 minutes to brown the underside.

Reduce heat to medium-low and cook for another 6-7 minutes, or until the potato mixture is firm on one side.

Using two spatulas, carefully flip the pancake over.

Add the remaining 2 tablespoons of butter (or 1 tablespoon each of butter and olive oil) under the pancake.

Cook for another 5-7 minutes, or until the pancake is set and done to the desired crispness.

Season the top with more black pepper, if desired.

Serve hot.