In a 12.5-in diameter round or 15x10-inch rectangle baking dish, combine the sliced peaches, lemon juice, and ¼ cup maple syrup, tossing gently until just combined.
In a large bowl, whisk the eggs, then add the coconut milk and 2 tablespoons maple syrup, whisking again. Add the oat flour, salt, and baking powder, stirring until just incorporated.
Pour the batter over the peaches in an even layer, covering them as best you can. It's okay if some peaches peek through the batter. Place the dish on a baking sheet to catch any drips that might bubble over, and then bake, uncovered, for 45 minutes.
Remove from the oven, brush the top with melted coconut oil, then return to the oven and bake 10-15 minutes more, or until the juices are bubbling and the top is slightly golden.
*Make your own oat flour for this recipe by placing 2 cups whole rolled oats in a blender and blending until a coarse flour forms. You can also purchase pre-made oat flour at many grocery stores and natural food markets or online.If you don't like the texture of peach skins in the cobbler, simply peel and proceed with the recipe. To peel, cut a small "x" shape into the skin at the bottom of each peach. Gently drop the peaches into gently boiling water for 2-3 minutes. Remove and immediately plunge into ice water. When cool, strain from the water, then peel.Sprinkle a little raw sugar on top of the crust after brushing with coconut oil in step 5 for extra sweetness and to add a slight crunch.Frozen, defrosted peaches can also be used in place of fresh if making this cobbler out of season.