Grease a standard Bundt pan with 1 tablespoon butter (or baking spray if preferred), and ¼ cup cocoa powder, shaking out the excess.
In the bowl of a stand mixer fitted with a paddle attachment, beat the remaining 1 ¾ cups butter, granulated sugar, and vanilla until smooth.
Add the eggs and egg yolks one at a time, beating between each addition until smooth, and scraping down the sides of the bowl as needed.
Add 2 cups confectioners’ sugar and ¾ cup cocoa powder. Beat to combine.
Add the flour and 1 teaspoon kosher salt. Beat to combine.
Fold in toasted pecans, reserving about 2 tablespoons for topping the cake after glazing.
Portion batter evenly into prepared Bundt pan.
Bake for about 45 minutes, or until the internal temperature of the cake reaches about 180 F.
Let cake stand in the pan for at least 30 minutes on a cooling rack, then flip to unmold.
Prepare the glaze: Stir to combine the remaining ⅔ cup confectioners’ sugar, ¼ cup cocoa powder, ¼ teaspoon salt, and 1 tablespoon milk to combine. Add additional milk a splash at a time until the glaze is smooth and pourable.
Transfer the cake to a serving plate.
Drizzle glaze over the top of the cake.
Sprinkle the cake with reserved pecans, slice, and serve.