Using a knife or mandolin cut the potatoes into slices ⅛-inch (3 mm) thick.
On a parchment paper-lined baking sheet, sprinkle half of the Parmesan cheese and spread until it is evenly covering the parchment paper.
Place the potatoes over the parmesan so each potato is overlapping the previous potato both vertically and horizontally. Continue until the entire pan is filled with potatoes.
Sprinkle to rest of the Parmesan evenly over the potatoes. Season with 1 teaspoon of salt. Bake for 30 minutes, until golden and the potatoes are flexible and slightly crispy.
In a skillet heat 2 tablespoons of olive oil over medium heat. Once the oil begins to shimmer, add the onions, and cook until caramelized, about 15 minutes.
Add the beef break up and mix with the onion until cooked. Mix in the tomatoes, 3 tablespoons of parsley, paprika, 1 teaspoon of salt, and pepper. Stir, cooking until the beef is browned and cooked through. Remove from heat.
In a skillet heat 2 tablespoons of olive oil over medium heat. Add the spinach, cook until wilted. Add 1 teaspoon of salt and the garlic. Stir to combine. Remove from heat.
In a bowl combine the spinach mixture and the ricotta. Set aside.
Evenly spread the spinach mixture over the cooked potato sheet.
Evenly spread the beef mixture over the spinach. Sprinkle mozzarella over the beef.
Take one end of the potato sheet holding the parchment paper begin rolling upward, making sure the ingredients are not coming out the ends.
Once the it is completely rolled place the potato roll on the parchment paper and bake for 15 minutes.
Sprinkle with parsley for garnish. Slice and serve immediately.