Preheat the oven to 350°F. Grease and flour a 10-12 cup bundt pan
In a large bowl, whisk together the cake mix and pudding mix.
Add in the grapefruit juice, milk, oil, eggs, zest, vanilla, and salt.
Beat on medium speed for 2 minutes until smooth and luscious.
Pour the batter into the prepared pan and smooth the top.
Bake for 50-55 minutes or until a toothpick comes out clean (an instant read thermometer will register 200F)and the house smells divine.
Let cool in the pan for 10 minutes, then transfer to a wire rack to finish cooling.
Glaze
Whisk together the powdered sugar, grapefruit juice, zest, and salt until smooth. If it’s too thick, add a splash more juice.
Drizzle that goodness over the cooled cake like you’re baptizing a sinner. Go slow, let it soak in, and if you’re feeling sassy, double it and glaze it twice.
Notes
Storage:
Counter: Covered, 3 days max.
Fridge: Up to 5 days (but it dries out, so wrap it tight).
Freezer: Wrap in plastic + foil. Keeps for 2 months. Thaw on counter.
Tips:
Let the cake cool it in the pan for 15 to 20 minutes after it comes out of the oven, then run a knife carefully around the edges before inverting it onto a wire cooling rack. Make sure it's cooled completely before glazing.