Preheat your oven to 400°F and line a small baking sheet with parchment paper.
Scrub the russet potato clean, pierce it several times with a fork, and rub the skin with avocado oil and a pinch of sea salt.
Bake the potato for 45 to 50 minutes until the skin is crisp and the center is tender when pierced with a knife.
While the potato bakes, brown the ground turkey in a non-stick skillet over medium-high heat until no longer pink.
Add the fresh spinach to the skillet and sauté for 2 minutes until wilted, then season with garlic powder, salt, and pepper.
Once the potato is cool enough to handle, slice it in half lengthwise and carefully scoop out the flesh into a mixing bowl, leaving a thin wall against the skin.
Mash the potato flesh with the Greek yogurt until smooth, then fold in the cooked turkey and spinach mixture.
Spoon the filling back into the potato skins, top with shredded sharp cheddar cheese, and return to the oven for 5 minutes until the cheese is bubbly.
Garnish with thinly sliced green onions and serve immediately.