Preheat the oven to 325°F (165°C). Lightly grease a 9-inch springform pan and line the bottom with parchment paper for easier removal.
Wash and thoroughly dry the spinach, then finely chop it. If using frozen spinach instead, thaw it completely and squeeze out as much moisture as possible.
Drain the roasted red peppers thoroughly, pat them dry with paper towels, and finely chop them into small pieces.
Finely chop the parsley and dill, mince the garlic, and grate 1 teaspoon of lemon zest. Set the prepared herbs, garlic, and lemon aside.
Place the softened cream cheese in a large mixing bowl and beat on medium-low speed until smooth and free of noticeable lumps.
Add the Greek yogurt and mix gently until completely incorporated and creamy.
Add the eggs one at a time, mixing gently after each addition until just combined. Avoid overmixing once the eggs have been incorporated.
Add the minced garlic, parsley, dill, lemon zest, lemon juice, olive oil, oregano, black pepper, and salt. Mix gently until the seasonings are evenly distributed.
Fold the chopped spinach and roasted red peppers into the cream cheese mixture using a rubber spatula, making sure the vegetables are evenly distributed throughout the filling.
Add the crumbled feta and gently fold it into the mixture, leaving some slightly larger pieces intact for extra bursts of flavor.
Pour the completed filling into the prepared springform pan and spread the surface evenly with a rubber spatula.
Bake at 325°F (165°C) for 45–55 minutes, or until the edges are set and the center has a gentle wobble when the pan is carefully moved.
Turn off the oven, leave the cheesecake inside with the door slightly open for about 10 minutes, then remove it and allow it to cool at room temperature for at least 30–45 minutes.
Refrigerate the cheesecake for at least 2 hours, preferably longer, until thoroughly chilled and firm enough to slice cleanly.
Carefully run a thin knife around the edge, release the springform pan, and cut the cheesecake into 10 wedges. Garnish with fresh parsley, dill, lemon zest, feta, or a light drizzle of olive oil before serving if desired.