Grease an 8x10x2 baking dish*, or one of similar size, with coconut oil. Preheat the oven to 375 degrees Fahrenheit.
In a medium bowl, add almond flour, white rice flour, cane sugar, ground cinnamon, and salt. Whisk to combine. Add the coconut oil to bowl in small pieces, then mix with your hands until the mixture makes small pea-sized balls or stays together when pinched. (If you feel mixture is not coming together, add a little more coconut oil.) Add almond extract and mix again. Place in the refrigerator for 10 minutes.
Add your raspberries and peaches to the prepared baking dish. Next, sprinkle lemon juice, salt, cinnamon, coconut sugar, and cornstarch over fruit. Gently mix until evenly coated.
Scatter topping evenly over prepared fruit. I like to press some of the topping into little pieces or balls for variation and streusel-like chunks. Scatter slivered almonds over top. Bake for 30 to 40 minutes, or until fruit is bubbling and topping has started to brown.
Allow to cool for a few minutes, then serve immediately. Best with ice cream or coconut whipped cream. The crumble is best served warm after baking, but can be stored in an airtight container in the refrigerator for up to 3 days.