Pre-heat oven to 350. Pull out a deep oven-safe pan. I used a smaller 7×7 style, but you could use a 9×12 and just double the amount of fruit to 8 cups. The crumble topping recipe will work for either size (it’ll just be thicker with the smaller pan!).
Mix chopped fruit into a large bowl with all other filling ingredients. Toss well to coat and set aside.
In another bowl, combine maple syrup, melted coconut oil, salt, and vanilla.
Pulse nuts of choice in a food processor, or simply chop, until a small crumb like texture forms (a few seconds). Pour into the wet ingredients along with everything else (oats, coconut flakes, almond flour, and flaxseed meal–if using. Mix everything together well, until the dry ingredients soak up the wet.
Pour the fruit into the pan, BUT tilt the bowl up a little or use a sieve so the liquid in the bottom is left behind. You can include it, but expect a more watery filling.
Scoop the topping over the top until it’s covered. Bake for about 15-20 minutes (with a smaller pan) or closer to 25-30 for a larger pan. Keep an eye; when the top is turning golden brown and the fruit is bubbling on the sides, you’re good!
Let sit for 5-10 minutes and then enjoy. Can be kept in the fridge for up to a week. Best when reheated in the oven for a crisp top, but can’t say I haven’t dug in (straight out of the fridge) for breakfast!