In a medium bowl, combine the peaches, nectarines, plums, lemon zest, lemon juice, cinnamon, nutmeg, coconut sugar and tapioca flour. Stir to combine and coat all of the fruit evenly. Pour all of the fruit filling into an 8x8” (or similarly sized) pan and set aside while preparing the crisp topping.
In a separate bowl, combine the almond flour, tapioca flour, rolled oats, and coconut sugar. Add the coconut oil and using a pastry cutter, two forks, or your hands, work the coconut oil into the flour until it comes together into a course meal with no dry flour remaining. Toss in the pecans.
Cover the fruit evenly with the oat topping and bake for 35-40 minutes, or until golden brown and bubbling. If topping is browning too quickly, tent the pan with aluminum foil halfway through to prevent burning.
Let cool slightly before serving warm. Store leftovers in the refrigerator for up to 3 days.
Notes
This recipe doubles very well. If doubling, bake in a 9x13" pan and add about 10 minutes to the baking time.