Preheat your oven to 350°F and line a baking sheet with parchment paper. While the oven heats, gather all your ingredients and have them ready to go—this quick prep ensures you can mix the dough efficiently once everything is measured out.
In a large mixing bowl, combine the mashed bananas, peanut butter, ground cinnamon, and salt. Mix until well combined, then fold in the quick oats until fully incorporated—the dough will be thick and slightly moist. Finally, gently fold in the chocolate chips, being careful not to crush them. I always recommend using very ripe bananas with brown spots here, as they provide natural sweetness and moisture without needing added sugar.
Using a 1.5 tablespoon cookie scoop or two spoons, portion the dough into evenly-sized balls and place them about 2 inches apart on the prepared baking sheet. Gently flatten each cookie to about 1/4-inch thickness using the back of a spoon or your palm—this helps them bake more evenly and develop better texture.
Place the baking sheet in the preheated 350°F oven and bake for 8-10 minutes, until the edges are lightly golden and the centers are just set. I like to check them around the 8-minute mark since oven temperatures vary—they should still feel slightly soft in the center when you remove them, as they'll continue to firm up as they cool.
Remove the baking sheet from the oven and let the cookies cool on the sheet for 2-3 minutes to firm up slightly, then serve warm or transfer to a cooling rack for complete cooling. These cookies are best enjoyed fresh and warm, when the peanut butter and chocolate are still slightly soft.