1. Preheat the oven to 350°F.
2. Place butter, sugars, eggs and milk in the bowl fitted with the kneading/ crushing blade. Launch the P3 pastry program. Peel and roughly chop the bananas.
3. At the end of the program, add bananas, flour, baking powder, baking soda, salt and all the chocolate chips, except for 1 Tbsp. Mix at speed 6 for 40 seconds. Scrape down the sides of the bowl and mix at speed 6 for another 10 seconds.
4. Line the bottom of a 9 x 5-inch loaf pan with parchment paper. Pour the mixture into the pan; sprinkle with remaining chocolate chips and bake for 1 hour to 1 hour 15 minutes.
5. Cool in the pan for 10 minutes. Run a knife around the edge of the pan to loosen. Turn onto a cooling rack and cool for at least 1 hour.