Blend the bananas, vanilla, cinnamon, Greek yogurt and milk together with an immersion blender, food processor, or a high-powered blender until well combined.
2 medium bananas, 2 teaspoons vanilla extract, 1/4 teaspoon cinnamon, 1/2 cup (120 grams) plain yogurt, 1/4 cup (60 ml) milk, 2-4 tablespoons whipping cream