Place potatoes in a large pot and cover with cold water. Bring to a boil, cooking for 10 to 15 minutes or until a fork easily pierces through the middle of the potato. Remove potatoes from water and allow to cool on a plate.

In a large skillet, heat olive oil over medium-low heat and sauté the onions. Add the sugar, 1 teaspoon salt, and ½ teaspoon pepper. Sauté until onions are golden brown, stirring frequently, about 20 minutes.

Peel potatoes and place in a large bowl. Mash with a fork or potato masher. Add coconut oil, 1 teaspoon salt, and ½ teaspoon pepper, or more to taste. Mix in the onions and stir until everything is combined.

Place a crêpe cooked side up on a clean surface. Place 3 to 4 tablespoons of potato filling towards the bottom of the crêpe. Fold the lower edge of the crêpe over the filling, fold the sides inwards, and roll up over the filling, tucking the edges in as you roll. Repeat with the remaining crêpes and filling.

Once the blintzes are assembled, heat the oil in a skillet over medium heat until hot. Carefully place 3 to 4 blintzes seam side down and fry for 1½ to 2 minutes on each side, until they are golden brown.

Serve warm, garnished with chopped parsley.