Preheat oven to 350 degrees F (176 degrees C). Grease a 9-inch cast iron skillet, and wash the blueberries.
In a large bowl, combine blueberries, brown sugar, cinnamon, allspice, and chopped rosemary.
4 cup blueberries, ¼ cup brown sugar, ¾ teaspoon cinnamon, ½ teaspoon allspice, 1½ teaspoon rosemary
Combine the gluten free rolled oats, gluten free flour (or almond flour), sliced almonds, cinnamon, honey, salt, and melted butter in a mixing bowl.
¾ cup rolled oats, ¼ cup flour, ¼ cup almonds, ¼ teaspoon cinnamon, ¼ cup honey, ⅛ teaspoon salt, 3 tablespoon butter
Combine with a spoon or fork until the mixture comes together into a texture that resembles dry oatmeal cookie dough.
Pour the blueberry mixture into the prepared cast iron skillet. You can use any oven safe skillet or baking dish.
Using your hands, crumble the oatmeal topping over the blueberry filling in the skillet.
Bake in the oven for 30 minutes, or until the crisp topping is nicely browned and crisp.
Lay a piece of aluminum foil loosely over the top to prevent over browning, and bake for an additional 10 to 15 minutes until the blueberry crisp is bubbly.
Remove from oven and cool for 5 to 10 minutes before serving. Enjoy!