Preheat the oven to 450°F.
In a 10-inch skillet, heat 2 tablespoons of the olive oil over medium heat. Add the artichokes, garlic, and onion and cook, stirring often, until softened and lightly caramelized, 6 to 8 minutes.
Meanwhile, in a large bowl, whisk together the eggs and sour cream until smooth, followed by 1 cup of the Parmesan, the parsley, dill, salt, and pepper to combine. Stir in the spinach and the cooked artichoke mixture.
Return the skillet to medium heat with the remaining 2 tablespoons of olive oil. Pour in the egg mixture and cook, stirring occasionally, for 2 minutes. Sprinkle the remaining ½ cup of Parmesan on top. Transfer to the oven and bake for 15 minutes, until golden and set. Let cool slightly, then transfer to a platter. Slice and serve.
