Preheat the oven to 325F. Grease and flour a bundt pan or generously spray with nonstick spray.
In a large bowl, beat cream cheese and 1 1/4 cups butter until smooth and creamy, about 3 minutes.
Add sugar gradually and beat until light and fluffy, about 4 minutes.
Add eggs one at a time, beating well after each addition.
Beat in vanilla extract until incorporated.
In a separate bowl whisk together cake flour and buttermilk. With mixer on low, alternate adding flour and buttermilk to batter until just combined.
Pour batter into the prepared pan. Bake for 1 hour to 1 hour and 15 minutes, until a toothpick inserted into the center comes out with a few crumbs. Cool in pan 15 minutes then invert to a rack.
To make glaze, melt 1/2 cup butter with 1 cup sugar and 1 tablespoon vanilla in a saucepan over medium heat until smooth. Remove from heat and stir in chopped pecans.
While the cake is still warm, poke holes in the top with a fork and brush with half of the glaze. Let cool slightly, then flip and brush the other side with the remaining glaze. Serve after it sets for a bit.
Notes
Best served slightly warm or at room temperature. Store in airtight container for up to 3 days.