Preheat your oven to 350°F. Grease and flour a bundt pan like your cake’s life depends on it.
In a big bowl, mix mashed bananas, sugar, sour cream, butter, eggs, and vanilla. Stir until smooth-ish.
Sprinkle in flour, baking soda, and salt. Mix just until combined. No overthinking, no overmixing.
Pour the batter into your prepared bundt pan. Smooth the top with a spoon (or not, no pressure).
Bake for 60–65 minutes. When a toothpick comes out clean, you're golden.
Let the cake cool in the pan for 10 minutes. Flip it onto a wire rack and pretend you’re not dying to slice into it immediately.