01 -
Preheat oven to 400°F (200°C). Wash and scrub sweet potatoes thoroughly. Pierce each potato several times with a fork, then arrange on a parchment-lined baking sheet. Bake for 45 to 60 minutes, or until tender when pierced with a knife.
02 -
While sweet potatoes bake, heat olive oil in a large skillet over medium heat. Add diced onion and sauté for 3 to 4 minutes until soft and translucent. Stir in minced garlic and cook 1 minute. Add sliced mushrooms and cook for 5 to 7 minutes, until they release moisture and begin to brown. Add spinach and sauté until wilted, about 2 to 3 minutes.
03 -
Stir in finely chopped rosemary, salt, black pepper, and red pepper flakes if using. Cook 1 additional minute. Remove skillet from heat and fold in crumbled feta cheese and lemon zest, mixing until just incorporated.
04 -
When sweet potatoes are tender, remove from oven and let cool slightly. Slice each potato lengthwise down the center, leaving the base intact. Gently press ends towards each other to create an opening for stuffing.
05 -
Generously spoon the mushroom, spinach, and feta filling into each sweet potato. Top with chopped walnuts and drizzle with a little olive oil if desired. Serve hot.