I've included weight as well as dry measures for the oats and flour. If you have a scale, I recommend weighing these two ingredients instead of scooping them. I find that weighing ingredients for baked goods makes recipes infinitely more reliable.
½cupunsalted buttersoftened (plus more for greasing loaf pan)
3very ripe bananasmashed
Preheat the oven to 350°F.
Grease a loaf pan with butter.
In a medium bowl whisk together flour, baking powder, baking soda and salt. Stir in oats.
In the bowl of a stand mixer, fitted with the paddle attachment, beat honey and butter on medium-high speed until fluffy, about 2 minutes. Add eggs and vanilla; mix just until combined. Add mashed bananas and milk; mix just until combined.
Mixing on low speed, add dry ingredients in two additions, scraping down sides with a spatula as needed.
Pour batter into the prepared loaf pan and bake 60-70 minutes, or until a knife inserted in the center comes out clean.
Cool bread in the pan on cooling rack for 15 minutes. Remove loaf from pan and place back on cooling rack to cool completely. Slice and serve or for best results, wrap tightly with plastic wrap and refrigerate overnight. Then slice, toast and serve warm with butter.