01 - Preheat oven to 400°F. Scrub the sweet potatoes and pierce each several times with a fork.
02 - Place sweet potatoes on a baking tray lined with parchment paper. Bake for 45-50 minutes, or until tender when pierced with a knife.
03 - Heat olive oil in a skillet over medium heat. Add garlic and sauté until fragrant, about 30 seconds.
04 - Add spinach and cook, stirring, until wilted for 2-3 minutes. Season with salt, pepper, and nutmeg. Remove from heat and allow to cool slightly.
05 - In a bowl, combine ricotta, sautéed spinach mixture, Parmesan, and milk. Stir until creamy and well-mixed. Adjust seasoning to taste.
06 - When sweet potatoes are ready, let them cool for 5 minutes. Slice each potato down the center without cutting all the way through and gently fluff the insides with a fork.
07 - Spoon the creamy spinach ricotta filling into each potato. Return to the oven for 5 minutes to heat through if desired. Garnish with chopped parsley and serve warm.