Preheat oven to 170°C and prepare 12 muffin cups*.
Mash the bananas and dice the apples.
Then mix wet into dry ingredients, do not over-mix (I use a spatula instead of whisk).
Fold in apples.
Divide dough over 12 muffin cups.
Bake for about 25 minutes until golden brown and a toothpick inserted in the middle comes out clean.
*I use silicone muffin cups, but you can of course use paper cups or grease a muffin tin.