Meet your new favorite way to eat your apple a day.
Preheat the oven to 350°. Using a small sharp knife, score the cut sides of the apples in a crosshatch pattern. Arrange the apples in a muffin tin, cut-sides up. Brush with the melted butter. In a bowl using your fingertips, blend the panko, cold butter, and 3/4 cup cheese; season. Mound on the apples; bake until tender, 25 minutes. Top with more cheese and the bacon. Broil until the cheese melts, about 3 minutes. Garnish with the sour cream and chives.