This is an excellent banana bread recipe. It's quite old so all in Imperial measurements, but easily converted.
Makes two small loaves or one big one. Tins need to be lined.
Preheat oven to 190C.
Beat together all the following - I use my trusty hand-held electric mixer and a large bowl.
4 ozs butter, at room temperature
7ozs soft brown sugar (e.g. Muscovado)
2 eggs
2 ripe bananas, mashed (I often add more if they need using up)
Lemon juice (something like juice of half a lemon, add more for more bananas)
8 ozs plain flour
2 tsp baking powder
Half a tsp of salt (I usually forget to add this)
Once well mixed, you can add one or more of the following:
Raisins or sultanas
I usually add some chopped walnuts if I have them to hand.
Never tried this with chocolate chips, but that could work.
Fill the tins and bake for at least 30 minutes (small loaves). Should be done in 40 minutes. One big loaf (2lb tin) would take a bit longer. Keeps well for a few days in an airtight container. Freezes extremely well.