4 t olive oil 1 medium onion, coarsely chopped 1 pound ground beef 14 (8-oz package) manicotti 1 (15-oz) container whole-milk ricotta 3 c shredded mozarella 1 c grated Parmesan 2 T chopped fresh Italian parsley leaves 2 garlic cloves, minced 3 c marinara sauce 2 T butter, cut into pieces Heat a heavy medium skillet over medium heat. Add 1 teaspoon of the oil, onion and ground beek. Season with salt and pepper. Saute until the meat browns and the onion is translucent, about 5 minutes. Remove from the heat, and cool. Brush 1 teaspoon of oil over a large baking sheet. Cook the manicotti in a large pot of boiling salted water until slightly softened, but still very firm to the bite, about 4-6 minutes. Using a slotted spoon, transfer the manicotti from the pot to the oiled baking sheet and cool. Meanwhile, combine the ricotta, 1 1/2 to 2 cups mozzarella cheese, 1/2 cup Parmesan, and parsley. Add the garlic, salt, and pepper to taste, and mis. Stir the cooled meat mixture into the cheese mix...