Preheat the oven to 350F degrees. Line a 9x5 inch loaf pan with parchment paper or grease and flour. Set aside.

In a large bowl using a stand or hand-held electric mixer, cream together the peanut butter and brown sugar on medium speed until well combined and no sugar lumps remain. Add in the eggs and vanilla and continue mixing until combined.

In a separate medium sized bowl, whisk together the flour, baking powder and salt. Then in a large liquid measuring cup add the yogurt and milk, then stir or whisk them together. With the mixer on low speed, add in about ½ of the flour mixture followed by ½ of the milk & yogurt mixture. Turn off the mixer and scrape down the sides of your bowl as needed. Once combined, repeat with the rest of the flour mixture and wet ingredients. Be careful not to overmix. Finally, turn off the mixer and stir in the chocolate chips using a large wooden spoon or rubber spatula.

Pour or spoon the batter into your prepared loaf pan and sprinkle the top with chocolate chips if desired. Bake for 50-60 minutes. When the loaf is ready, an inserted toothpick should come out clean or with a crumbs. Check the loaf around 45 minutes, and if the top is getting too browned tent a piece of aluminium foil over the top of the pan. Once finished cooking, allow the loaf to cool completely before cutting in.