Preheat your oven to 350°F (175°C). Grease and flour a baking pan or prepare it with parchment paper to prevent sticking.

In a food processor, combine toasted pecans, dark brown sugar, and a pinch of cinnamon. Pulse until the pecans are finely chopped. Set this pecan mixture aside.

In a mixing bowl, cream together unsalted butter and granulated sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Mix in the vanilla extract.

In a separate bowl, sift together the all-purpose flour, baking powder, and a pinch of salt. Gradually add this dry mixture to the wet ingredients, alternating with the sour cream and freshly brewed coffee. Mix until just combined.

Pour half of the batter into the prepared baking pan. Sprinkle a layer of the pecan filling over this batter. Then pour the remaining batter on top of the pecan layer, spreading it evenly.

Place the pan in the preheated oven and bake for about 45-55 minutes or until a toothpick inserted into the center comes out clean.

While the cake is baking, prepare the glaze by mixing confectioners' sugar with a small amount of water, adjusting until you reach a thick yet pourable consistency. Add a touch of cinnamon for flavor.

Once the cake is baked and cooled for a few minutes, drizzle the glaze over the top. Sprinkle some additional chopped toasted pecans on top if desired.

Allow the cake to cool completely before slicing and serving.