Simple Healthy(ish) Crumble

Squish 5 ripe bananas in a pie dish. Sprinkle with a little bit of sugar. Put in some frozen or fresh berries and mix. Sprinkle instant oats and small walnut pieces on top. Squish some soft butter chunks in with the oats/nuts and push them down a little bit into the berries/bananas. I didn't measure anything and I doubt it matters too much how much of anything you choose to put in. Bake at 350 until top is golden (it takes a long time because of how moist the bananas are), about 45 min. or an hour. Viola, easy crumble. Pretty healthy, as desserts go.