Preheat the oven to 350 degrees F (175 degrees C). Coat a 9x13-inch baking pan with cooking spray; set aside.

Combine brown sugar, flour, and pumpkin pie spice in a medium bowl. Cut in 4 tablespoons cold butter using a fork or pastry blender until it resembles coarse crumbs. Set streusel aside.

Beat cake mix and 4 tablespoons softened butter together in a large bowl with an electric mixer on medium speed until well combined. Add eggs, one at a time, mixing well after each addition. Add pumpkin purée and cinnamon; mix until well blended, about 3 minutes. Stir in pecans.

Pour batter into the prepared pan, spreading evenly. Sprinkle streusel topping over batter.

Bake in the preheated oven until a toothpick inserted into center comes out clean, 40 to 45 minutes. Cool cake before serving for about 5 minutes.