Preheat your oven to 325 degrees and grease your bundt pan with oil or butter and some flour.
Combine all dry ingredients in one large mixing bowl, including flour, sugar, baking soda, and cinnamon. Set aside.
In another mixing bowl, mash bananas, leaving some bits and chunks of banana in the batter. Add butter, eggs, and Greek yogurt, mix thoroughly. Fold in half of the sliced peaches, then pour the batter into bundt pan.
Layer the remaining sliced peaches to the top of the batter evenly, all the way around the pan. Note, the peaches will sink into the batter once it starts baking. Bake for 45-50 minutes.
Allow the bread to cool thoroughly and gently loosen around the edges with a butter knife. Flip the pan upside down onto a large plate to remove the bread. Dust with powdered sugar and slice to serve.