Non-stick baking spray
2 (7 oz.) packages Martha White Pumpkin Spice Muffin Mix
5 tablespoons chilled unsalted butter, cubed
½ cup sour cream
⅔ cup chocolate chips
1 cup chocolate chips
2 tablespoons unsalted butter
1 tablespoon whole milk
Heat oven to 400°F. Spray a large baking sheet with non-stick spray.
Add the muffin mix to a large bowl. Using your fingers or a pastry cutter, work the butter into the muffin mix until it is crumbly.
Stir in sour cream and chocolate chips until the mixture forms large clumps. Turn onto a lightly floured surface and knead gently until the dough just comes together, then pat into an 8-inch circle. Cut into 6 wedges.
Place wedges on the prepared pan. Bake until puffed and golden, about 15 minutes. Transfer to a baking rack to cool.
Add chocolate chips and butter to a small, microwave-safe bowl. Microwave on high in 15-second increments, stirring between each one, until smooth. Stir in milk. Drizzle the mixture over cooled scones and let rest until set, at least 15 minutes.