I'm sure you could make a variation in the oven - I suppose they'd be more chewy, a bit like a muesli bar. Then they'd keep for a few days I'd say, and you could probably freeze them. Or you could try these banana cookies:
Ingredients
• 3 ripe bananas
• 2 cups rolled oats
• 1 cup dates, pitted and chopped
• 1/3 cup vegetable oil
• 1 teaspoon vanilla extract
Directions
1. Preheat oven to 350 degrees F (175 degrees C).
2. In a large bowl, mash the bananas. Stir in oats, dates, oil, and vanilla. Mix well, and allow to sit for 15 minutes. Drop by teaspoonfuls onto an ungreased cookie sheet.
3. Bake for 20 minutes in the preheated oven, or until lightly brown.
I've only made them once and changed the recipe, so I only used 1/4 cup of oil. I added raisins instead of dates to one half of the mix, and made the other half with no dried fruit at all (wasn't sure how she'd handle the raisins at that stage). Oh, and I added cinnamon instead of vanilla. Ok, so basically not this recipe at all, but it's what I started with
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. They were pretty good, even the plain banana ones were plenty sweet, and they froze well.