Preheat Oven:
Preheat oven to 375°F (190°C). Grease a 9-inch pie dish or similar baking dish.

Cook Cabbage & Onion:
In a large skillet, melt butter over medium heat. Add onions and sauté until translucent, about 3–4 minutes. Add cabbage and cook until softened and slightly browned, about 10 minutes. Remove from heat and let cool slightly.

Prepare Pie Mixture:
In a large bowl, beat eggs. Stir in sour cream, cheese, flour, salt, pepper, and dill. Add cooked cabbage mixture and combine well.

Bake Pie:
Pour mixture into prepared pie dish. Bake for 35–40 minutes or until set and golden on top.

Make Dill Cream Sauce:
While pie bakes, whisk together sour cream, mayonnaise, dill, lemon juice, salt, and pepper in a small bowl.

Serve:
Let pie cool for a few minutes before slicing. Serve with dill cream sauce on the side or drizzled over the top.