Preheat your oven to 350°F (175°C). Grease your loaf pan with a little melted butter or line it with parchment paper for easy removal.
In a large mixing bowl, mash the ripe bananas until smooth. Then add the Greek yogurt, melted butter (or coconut oil), maple syrup (or honey), eggs, and vanilla extract. Whisk until everything is well combined.
In another bowl, mix together the whole wheat pastry flour, baking soda, ground cinnamon, and salt. Stir gently to combine.
Slowly add the dry ingredients into the wet mixture. Stir gently until just combined; be careful not to overmix. A few lumps are okay!
Using a rubber spatula, gently fold in the chocolate chunks until evenly distributed throughout the batter.
Pour the batter into the prepared loaf pan, smoothing the top with the spatula. Bake in the preheated oven for 50-60 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
Once baked, remove from the oven and let the bread cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely. Slice and enjoy your Chocolate Chunk Greek Yogurt Banana Bread warm or at room temperature!