Preheat your oven to 350ºF and prepare an 8x8 or 9x9 inch pan with aluminum foil or parchment paper, lightly greased.

In a mixing bowl, blend the flour, salt, and cocoa powder; set aside.

In a small saucepan over low heat, melt the unsweetened chocolate and butter, stirring occasionally.

In a larger mixing bowl, use an electric mixer to beat sugar, eggs, and an additional yolk until the mixture turns pale yellow and doubles in volume.

Combine the melted chocolate with the egg mixture, add vegetable oil and vanilla extract, stirring to combine.

Gently fold the flour mixture into the wet ingredients until just combined. Avoid overmixing.

Set aside 1/2 cup of batter. Pour the remaining batter into the pan.

In a separate bowl, mix cream cheese, egg, pumpkin puree, sugar, and spices with an electric mixer until smooth.

Spread the cream cheese filling over the brownies and use a toothpick to create swirls. Drop dollops of the reserved 1/2 cup of batter and swirl again with the toothpick.

Bake for 40-45 minutes in a glass pan or 35-40 minutes in a metal pan, or until a toothpick comes out clean from the center.

Allow the brownies to cool completely before cutting.