Preheat your oven to 350°F (175°C). Place chopped pecans and 2 tablespoons of unsalted butter in a skillet over medium heat. Stir frequently until the pecans are fragrant and lightly toasted, about 5-7 minutes. Set aside to cool.

In a large bowl, cream together the softened butter, butter-flavored shortening, and granulated sugar. Beat until light and fluffy, about 5 minutes. Add in the eggs, one at a time, beating well after each addition. In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add the dry ingredients to the creamed mixture, alternating with the milk, beginning and ending with flour. Mix just until combined. Stir in vanilla extract and the toasted pecans.

Pour the batter into a greased and floured 10-inch bundt or tube pan. Level the batter with a spatula. Bake for 70-80 minutes, or until a toothpick inserted in the center comes out clean. Cool in the pan for 10 minutes, then turn out onto a wire rack to cool completely.

In a small saucepan, combine brown sugar and ¼ cup unsalted butter. Cook over medium heat, whisking constantly, until the mixture is smooth and starts to bubble. Remove from heat and whisk in heavy cream and vanilla extract. Gradually whisk in powdered sugar until the glaze is thick but pourable (add more to thicken if needed). Let the glaze cool for about 5-10 minutes, then pour over the cooled cake.

Let the glaze set for a few minutes before slicing. Serve with a scoop of vanilla ice cream or a dollop of whipped cream if desired!