Slice off the top of the sourdough loaf about an inch down to create a lid and scoop out the soft bread from the interior.
In a medium mixing bowl, combine the chopped spinach, diced artichoke hearts, softened cream cheese, sour cream, shredded mozzarella, grated Parmesan, minced garlic, and dried oregano. Stir well and add salt and pepper to taste.
Stuff the hollowed-out sourdough loaf with the filling, packing it in tightly.
Brush the outside of the stuffed bread with olive oil.
Place the stuffed bread on a baking sheet and bake for about 25-30 minutes until golden brown and the cheese is bubbling.
Remove from the oven and let cool slightly. Garnish with chopped fresh parsley.
Slice into wedges and serve warm with the scooped-out bread on the side.
Notes
Serve warm with the scooped-out bread for dipping.