Preheat oven to 350 degrees.
Grease a 9-inch pie pan with butter or coconut oil spray. Place atop a parchment-lined sheet pan to catch any boil-overs.
To a large bowl, add the raspberries and peaches with remaining fruit mixture ingredients. Mix gently to combine then let sit to macerate while preparing the cobbler batter.
In a medium bowl, whisk together maple sugar with melted butter, cream and almond extract until well incorporated.
To the wet batter, fold in the GF flour, baking powder and salt, careful not to overmix.
Add half of batter to baking dish, smoothing evenly then top with the macerated fruit mixture. Top with remaining batter, smoothing evenly, then sprinkle with slivered almonds.
Bake on the middle rack until golden and bubbling, 45-50 min, rotating pan 180 degrees, 1-2 times during cooking.
Serve warm with whipped cream or vanilla bean ice cream.