Preheat the Oven: Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan or line it with parchment paper.
Prepare Dry Ingredients: In a medium bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and optional cinnamon.
Cream Butter and Sugar: In a large bowl, beat the softened butter with an electric mixer until creamy. Gradually add the sugar and continue to beat until light and fluffy.
Add Eggs and Bananas: Beat in the eggs, one at a time, ensuring each is fully incorporated before adding the next. Mix in the mashed bananas until combined.
Mix in Sour Cream and Vanilla: Add the sour cream (or Greek yogurt) and vanilla extract, mixing until smooth.
Combine Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Be careful not to overmix.
Fold in Chocolate Chips: Gently fold the mini chocolate chips into the batter.
Bake: Pour the batter into the prepared cake pan and spread it evenly. Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
Cool and Serve: Allow the cake to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
Optional: Dust with powdered sugar or drizzle with a simple glaze if desired.