Heat the oven to 350°F and lightly grease a 1 1/2-quart shallow baking dish.
Beat softened cream cheese until lump-free. Add Greek yogurt 1/4 cup at a time, mixing completely smooth after each addition.
Stir in Buffalo sauce, garlic powder, onion powder and paprika until uniformly pale orange.
Fold in shredded chicken, 1 cup cheddar and half the scallions. Add Greek yogurt by the tablespoon only if unusually stiff.
Spread evenly in the prepared dish, top with remaining cheddar and set the dish on a rimmed sheet pan.
Bake 20 to 25 minutes, until the edges gently bubble, cheese melts and the center reaches 165°F.
Rest 5 minutes, top with remaining scallions and serve warm with vegetables, crackers or tortilla chips.
