01 - Preheat oven to 375°F. Lightly grease a small 1-quart baking dish with olive oil or cooking spray.
02 - Heat 1 tablespoon olive oil in a skillet over medium heat. Add minced garlic and sauté for 30 seconds until fragrant, taking care not to brown.
03 - Add chopped spinach to the skillet. Sauté for 2–3 minutes, tossing frequently, until completely wilted. Remove from heat and let cool for 2–3 minutes.
04 - In a large mixing bowl, combine crumbled feta, softened cream cheese, Greek yogurt, and half the shredded mozzarella. Mix with a spatula until mostly smooth and well incorporated.
05 - Fold in the cooled sautéed spinach, sliced pepperoncini, dried oregano, red pepper flakes (if using), and black pepper. Mix until evenly distributed throughout the cheese base.
06 - Spoon the mixture into the prepared baking dish, spreading evenly. Top with the remaining mozzarella cheese and drizzle with the remaining 1 tablespoon olive oil.
07 - Bake for 20–25 minutes until the dip is bubbly around the edges and the top is lightly golden. The cheese should be fully melted and the center hot throughout.
08 - Remove from oven and let rest for 5 minutes to set. Garnish with fresh parsley or dill and serve immediately with lemon wedges on the side.