Preheat the oven to 325°F (163°C) and grease/flour a 10–12 cup Bundt pan.
Cream butter, oil, and sugar until light and fluffy (about 4–5 minutes).
Add eggs one at a time, then mix in vanilla extract.
Whisk flour, baking powder, and salt in a separate bowl.
Alternate adding dry mixture with sour cream, milk, and crushed pineapple. Mix just until combined.
Pour batter into the pan, smooth the top, and bake for 75–85 minutes until golden and a toothpick comes out clean.
Cool in the pan for 15 minutes, then invert onto a wire rack to cool completely.
Whisk powdered sugar, cream (or milk), vanilla, and optional pineapple juice for the drizzle.
Drizzle over the cooled cake, slice, and serve.